0001558370-23-014269 | 10-Q | XBRL Viewer

Revenue from Contracts with Customers (Tables)

6 Months Ended

Jun. 30, 2023

Revenue from Contract with Customer [Abstract]

The Company is generally the principal in its customer contracts because it has control over the goods and services prior to their transfer to the customer, and as such, revenue is recognized on a gross basis. Sales and usage-based taxes are excluded from revenue. Revenue is recognized net of allowances for returns and any taxes collected from customers, which are subsequently remitted to governmental authorities. The table below presents the Company’s revenue disaggregated by revenue source (in thousands):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Product revenue:
Volume-related
Fuel sales⁽¹⁾	$	67,094	$	53,267	$	125,712	$	160,162
Change in fair value of derivative instruments⁽²⁾		(1,079)		3,600		(2,114)		1,068
RIN Credits		9,795		5,377		17,727		9,880
LCFS Credits		4,085		2,474		7,519		4,772
AFTC ⁽³⁾		(9)		5,059		222		9,555
Total volume-related product revenue		79,886		69,777		149,066		185,437
Station construction sales		5,967		5,852		9,294		9,919
Total product revenue		85,853		75,629		158,360		195,356
Service revenue:
Volume-related, O&M services		11,035		13,913		21,745		25,957
Other services		336		1,006		616		1,418
Total service revenue		11,371		14,919		22,361		27,375
Total revenue	$	97,224	$	90,548	$	180,721	$	222,731

(1)

Includes non-cash stock-based sales incentive contra-revenue charges associated with the Amazon Warrant. For the three and six months ended June 30, 2022, contra-revenue charges recognized in fuel revenue were $4.8 million and $8.5 million, respectively. For the three and six months ended June 30, 2023, contra-revenue charges recognized in fuel revenue were $13.9 Million and $27.7 million, respectively. See Note 14 for more information.

(2)

Represents changes in fair value of derivative instruments related to the Company’s commodity swap and customer fueling contracts associated with the Company’s Zero Now truck financing program. The amounts are classified as revenue because the Company’s commodity swap contracts are used to economically offset the risk associated with the diesel-to-natural gas price spread resulting from customer fueling contracts under the Company’s Zero Now truck financing program. See Note 6 for more information about these derivative instruments.

(3)	Represents the federal alternative fuel excise tax credit (“AFTC”). See Note 19 for more information.

Summary of contract balances

As of December 31, 2022 and June 30, 2023, the Company’s contract balances were as follows (in thousands):


	December 31,		June 30,
	2022		2023
Accounts receivable, net	$	91,430	$	74,746

Contract assets - current	$	6,063	$	8,724
Contract assets - non-current		2,976		2,699
Contract assets - total	$	9,039	$	11,423

Contract liabilities - current	$	5,477	$	3,329
Contract liabilities - non-current		—		—
Contract liabilities - total	$	5,477	$	3,329

Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Leases - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Leases
Sales-type lease, interest income	$ 0.1	$ 0.1	$ 0.2	$ 0.2

Short-Term Investments

6 Months Ended

Jun. 30, 2023

Investments, Debt and Equity Securities [Abstract]

Short-Term Investments

Note 5—Short-Term Investments

Short-term investments include available-for-sale debt securities, excluded from cash equivalents, that have maturities of one year or less on the date of acquisition and certificates of deposit. Available-for-sale debt securities are carried at fair value, inclusive of unrealized gains and losses. Unrealized gains and losses on available-for-sale debt securities are recognized in other comprehensive income (loss), net of applicable income taxes. Gains or losses on sales of available-for-sale debt securities are recognized on the specific identification basis.

The Company reviews available-for-sale debt securities for declines in fair value below their cost basis each quarter and whenever events or changes in circumstances indicate that the cost basis of an asset may not be recoverable and evaluates the current expected credit loss. This evaluation is based on a number of factors, including historical experience, market data, issuer-specific factors, economic conditions, and any changes to the credit rating of the security. As of June 30, 2023, the Company has not recorded a credit loss related to available-for-sale debt securities and believes the carrying values of its available-for-sale debt securities are properly recorded.

Short-term investments as of December 31, 2022 consisted of the following (in thousands):


			Gross
	Amortized		Unrealized		Estimated
	Cost		Gain (Loss)		Fair Value
Zero coupon bonds	$	74,524	$	(365)	$	74,159
U.S. government securities		64,861		19		64,880
Certificates of deposit		530		—		530
Total short-term investments	$	139,915	$	(346)	$	139,569

Short-term investments as of June 30, 2023 consisted of the following (in thousands):


			Gross
	Amortized		Unrealized		Estimated
	Cost		Gain (Loss)		Fair Value
U.S. government securities	$	137,999	$	40	$	138,039
Certificates of deposit		530		—		530
Total short-term investments	$	138,529	$	40	$	138,569

Debt - Riverstone Credit Agreement (Details) - Riverstone Credit Agreement	Dec. 22, 2022 USD ($)
Debt Instrument [Line Items]
Proceeds from loan	$ 150,000,000
Elected under SOFR
Debt Instrument [Line Items]
Applicable margin (as a percent)	7.25%
Floor rate (as a percent)	1.50%
Elected under ABR
Debt Instrument [Line Items]
Applicable margin (as a percent)	6.25%
Floor rate (as a percent)	2.50%
1 year to 18 months
Debt Instrument [Line Items]
Call premium (as a percent)	2.00%
18 months to 24 months
Debt Instrument [Line Items]
Call premium (as a percent)	2.50%
Thereafter
Debt Instrument [Line Items]
Call premium (as a percent)	3.00%
Federal Funds
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
SOFR
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Applicable margin (as a percent)	6.50%
ABR
Debt Instrument [Line Items]
Interest rate (as a percent)	5.50%

Land, Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Land, Property and Equipment
Land, property and equipment, gross	$ 769,768		$ 769,768		$ 721,912
Less accumulated depreciation	(477,305)		(477,305)		(457,844)
Total land, property and equipment, net	292,463		292,463		264,068
Capitalized software costs, net	35,800		35,800		35,300
Accumulated amortization on the capitalized software costs	33,000		33,000		32,100
Amortization expense related to the capitalized software costs	500	$ 300	900	$ 600
Amount included in accounts payable balances			12,700		12,900
Land
Land, Property and Equipment
Land, property and equipment, gross	3,620		3,620		3,476
LNG liquefaction plants
Land, Property and Equipment
Land, property and equipment, gross	96,607		96,607		94,790
Station equipment
Land, Property and Equipment
Land, property and equipment, gross	379,272		379,272		353,104
Trailers
Land, Property and Equipment
Land, property and equipment, gross	72,553		72,553		73,253
Other equipment
Land, Property and Equipment
Land, property and equipment, gross	99,795		99,795		106,184
Construction in progress
Land, Property and Equipment
Land, property and equipment, gross	$ 117,921		$ 117,921		$ 91,105

Condensed Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest in Subsidiary	Total
Beginning balance at Dec. 31, 2021	$ 22	$ 1,519,918	$ (771,242)	$ (1,622)	$ 8,335	$ 755,411
Beginning balance (in shares) at Dec. 31, 2021	222,684,923
Increase (Decrease) in Stockholders' Equity
Issuance of common stock		273				273
Issuance of common stock (in shares)	585,775
Repurchase of common stock		(3,001)				(3,001)
Repurchase of common stock (in shares)	(511,010)
Stock-based compensation		8,253				8,253
Stock-based sales incentive charges		1,721				1,721
Net loss			(24,191)		(385)	(24,576)
Other comprehensive income (loss)				249		249
Ending balance at Mar. 31, 2022	$ 22	1,527,164	(795,433)	(1,373)	7,950	738,330
Ending balance (in shares) at Mar. 31, 2022	222,759,688
Beginning balance at Dec. 31, 2021	$ 22	1,519,918	(771,242)	(1,622)	8,335	755,411
Beginning balance (in shares) at Dec. 31, 2021	222,684,923
Increase (Decrease) in Stockholders' Equity
Net loss					(512)	(37,938)
Other comprehensive income (loss)					0	(1,167)
Ending balance at Jun. 30, 2022	$ 22	1,533,118	(808,668)	(2,789)	7,823	729,506
Ending balance (in shares) at Jun. 30, 2022	222,177,172
Beginning balance at Mar. 31, 2022	$ 22	1,527,164	(795,433)	(1,373)	7,950	738,330
Beginning balance (in shares) at Mar. 31, 2022	222,759,688
Increase (Decrease) in Stockholders' Equity
Issuance of common stock		300				300
Issuance of common stock (in shares)	96,728
Repurchase of common stock		(3,121)				(3,121)
Repurchase of common stock (in shares)	(679,244)
Stock-based compensation		6,468				6,468
Stock-based sales incentive charges		2,307				2,307
Net loss			(13,235)		(127)	(13,362)
Other comprehensive income (loss)				(1,416)	0	(1,416)
Ending balance at Jun. 30, 2022	$ 22	1,533,118	(808,668)	(2,789)	7,823	729,506
Ending balance (in shares) at Jun. 30, 2022	222,177,172
Beginning balance at Dec. 31, 2022	$ 22	1,553,668	(829,975)	(3,722)	7,478	$ 727,471
Beginning balance (in shares) at Dec. 31, 2022	222,437,429					222,437,429
Increase (Decrease) in Stockholders' Equity
Issuance of common stock		332				$ 332
Issuance of common stock (in shares)	470,351
Shares withheld related to net share settlement		(175)				(175)
Stock-based compensation		6,096				6,096
Stock-based sales incentive charges		8,172				8,172
Net loss			(38,697)		(135)	(38,832)
Other comprehensive income (loss)				705		705
Ending balance at Mar. 31, 2023	$ 22	1,568,093	(868,672)	(3,017)	7,343	703,769
Ending balance (in shares) at Mar. 31, 2023	222,907,780
Beginning balance at Dec. 31, 2022	$ 22	1,553,668	(829,975)	(3,722)	7,478	$ 727,471
Beginning balance (in shares) at Dec. 31, 2022	222,437,429					222,437,429
Increase (Decrease) in Stockholders' Equity
Net loss					(320)	$ (55,318)
Other comprehensive income (loss)					0	2,403
Ending balance at Jun. 30, 2023	$ 22	1,582,009	(884,973)	(1,319)	7,158	$ 702,897
Ending balance (in shares) at Jun. 30, 2023	222,910,057					222,910,057
Beginning balance at Mar. 31, 2023	$ 22	1,568,093	(868,672)	(3,017)	7,343	$ 703,769
Beginning balance (in shares) at Mar. 31, 2023	222,907,780
Increase (Decrease) in Stockholders' Equity
Issuance of common stock		3				3
Issuance of common stock (in shares)	2,277
Stock-based compensation		6,093				6,093
Stock-based sales incentive charges		7,820				7,820
Net loss			(16,301)		(185)	(16,486)
Other comprehensive income (loss)				1,698	0	1,698
Ending balance at Jun. 30, 2023	$ 22	$ 1,582,009	$ (884,973)	$ (1,319)	$ 7,158	$ 702,897
Ending balance (in shares) at Jun. 30, 2023	222,910,057					222,910,057

Short-Term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 138,529	$ 139,915
Gross Unrealized Gain (Loss)	40
Gross Unrealized Gain (Loss)		(346)
Estimated Fair Value	138,569	139,569
Zero coupon bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		74,524
Gross Unrealized Gain (Loss)		(365)
Estimated Fair Value		74,159
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	137,999	64,861
Gross Unrealized Gain (Loss)	40	19
Estimated Fair Value	138,039	64,880
Certificates of deposit
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	530	530
Gross Unrealized Gain (Loss)	0
Gross Unrealized Gain (Loss)		0
Estimated Fair Value	$ 530	$ 530

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

+ Details

Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2023

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of compensation expense and related income tax benefit related to the stock-based compensation expense recognized

The following table summarizes the compensation expense and related income tax benefit related to the Company’s stock-based compensation arrangements recognized in the accompanying condensed consolidated statements of operations during the three and six months ended June 30, 2022 and 2023 (in thousands):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Stock-based compensation expense, net of $0 tax in 2022 and 2023	$	6,468	$	6,093	$	14,721	$	12,189

Schedule of warrant activity

The following table summarizes the Amazon Warrant activity for the six months ended June 30, 2023:


		Warrant
		Shares
Outstanding and unvested as of December 31, 2022		42,314,667
Granted		—
Vested		(1,763,112)
Outstanding and unvested as of June 30, 2023		40,551,555

Inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Inventory Disclosure [Abstract]
Raw materials and spare parts	$ 38,517	$ 37,144
Total inventory	$ 38,517	$ 37,144

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Income Taxes (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Income tax expense	$ (55)	$ 68	$ (119)	$ 117
Unrecognized tax benefits, increase from portion of AFTC revenue offset by the fuel tax			2,300
Tax benefit	$ 0	$ 0	$ 0	$ 0

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Cash, Cash Equivalents and Restricted Cash (Tables)

6 Months Ended

Jun. 30, 2023

Cash and Cash Equivalents [Abstract]

Schedule of cash and cash equivalents

Cash, cash equivalents and restricted cash as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Current assets:
Cash and cash equivalents	$	123,950	$	53,150
Restricted cash - standby letter of credit		2,000		2,012
Total cash, cash equivalents and current portion of restricted cash	$	125,950	$	55,162

Total cash, cash equivalents and restricted cash	$	125,950	$	55,162

Schedule of components of restricted cash

Cash, cash equivalents and restricted cash as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Current assets:
Cash and cash equivalents	$	123,950	$	53,150
Restricted cash - standby letter of credit		2,000		2,012
Total cash, cash equivalents and current portion of restricted cash	$	125,950	$	55,162

Total cash, cash equivalents and restricted cash	$	125,950	$	55,162

Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Payables and Accruals [Abstract]
Accrued alternative fuels incentives	$ 31,993	$ 34,239
Accrued employee benefits	4,863	5,128
Accrued gas and equipment purchases	13,480	22,008
Accrued interest	1,616	1,827
Accrued property and other taxes	3,525	3,782
Accrued salaries and wages	5,326	6,857
Embedded derivatives	80	0
Other	15,726	16,238
Total accrued liabilities	$ 76,609	$ 90,079

Inventory (Tables)

6 Months Ended

Jun. 30, 2023

Inventory Disclosure [Abstract]

Schedule of inventories

Inventory as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Raw materials and spare parts	$	37,144	$	38,517
Total inventory	$	37,144	$	38,517

Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Principal Balances
Total debt	$ 150,255	$ 150,093
Less amounts due within one year	(38)	(93)
Total long-term debt	150,217	150,000
Unamortized Debt Financing Costs
Total debt	5,380	4,529
Less amounts due within one year	0	0
Total long-term debt	5,380	4,529
Balance, Net of Financing Costs
Total debt	144,875	145,564
Less amounts due within one year	(38)	(93)
Total long-term debt	144,837	145,471
Riverstone Term Loan
Principal Balances
Total debt	150,000	150,000
Unamortized Debt Financing Costs
Total debt	5,380	4,529
Balance, Net of Financing Costs
Total debt	144,620	145,471
Other debt
Principal Balances
Total debt	255	93
Unamortized Debt Financing Costs
Total debt	0	0
Balance, Net of Financing Costs
Total debt	$ 255	$ 93

Fair Value Measurements

6 Months Ended

Jun. 30, 2023

Fair Value Disclosures [Abstract]

Fair Value Measurements

Note 7—Fair Value Measurements

The Company follows the authoritative guidance for fair value measurements with respect to assets and liabilities that are measured at fair value on a recurring basis and non-recurring basis. Under the standard, fair value is defined as the exit price, or the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants, as of the measurement date. The standard also establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. Observable inputs are inputs developed based on market data obtained from sources independent of the Company that market participants would use in valuing the asset or liability. Unobservable inputs are inputs that reflect the Company’s assumptions about the factors market participants would use in valuing the asset or liability developed based upon the best information available in the circumstances. The hierarchy consists of the following three levels: Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities; Level 2 inputs include quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active, and inputs (other than quoted prices) that are observable for the asset or liability, either directly or indirectly; and Level 3 inputs are unobservable inputs for the asset or liability. Categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement.

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The Company’s U.S. government issued debt securities are classified within Level 1 because they are valued using the most recent quoted prices for identical assets in active markets. Zero coupon bonds and certificate of deposits are classified within Level 2 because they are valued using the most recent quoted prices for identical assets in markets that are not active and quoted prices for similar assets in active markets.

The Company used the income approach to value its outstanding commodity swap contracts and embedded derivatives in its fueling agreements under the Zero Now truck financing program (see Note 6). Under the income approach, the Company used a discounted cash flow (“DCF”) model in which cash flows anticipated over the term of the contracts are discounted to their present value using an expected discount rate. The discount rate used for cash flows reflects the specific risks in spot and forward rates and credit valuation adjustments. This valuation approach is considered a Level 3 fair value measurement. The significant unobservable inputs used in the fair value measurement of the Company’s derivative instruments are Ultra-Low Sulfur Diesel (“ULSD”) forward prices and differentials from ULSD to Petroleum Administration for Defense District (“PADD”) regions. Significant increases (decreases) in any of those inputs in isolation would result in a significantly lower (higher) fair value measurement. Generally, a change in the ULSD forward prices is accompanied by a directionally opposite but less extreme change in the ULSD-PADD differential.

The Company estimated the fair value of its outstanding commodity swap contracts based on the following inputs as of December 31, 2022 and June 30, 2023:


	December 31, 2022			June 30, 2023
Significant Unobservable Inputs	Input Range	Weighted Average		Input Range	Weighted Average
ULSD Gulf Coast Forward Curve	$2.35 - $2.59	$	2.48	$1.98 - $2.23	$	2.13
Historical Differential to PADD 3 Diesel	$0.88 - $1.62	$	1.13	$0.92 - $1.62	$	1.14
Historical Differential to PADD 5 Diesel	$1.89 - $3.00	$	2.30	$1.89 - $3.02	$	2.36

The Company estimated the fair value of embedded derivatives in its fueling agreements under the Zero Now truck financing program based on the following inputs as of December 31, 2022 and June 30, 2023:


	December 31, 2022			June 30, 2023
Significant Unobservable Inputs	Input Range	Weighted Average		Input Range	Weighted Average
ULSD Gulf Coast Forward Curve	$2.35 - $2.59	$	2.48	$1.98 - $2.23	$	2.13
Historical Differential to PADD 3 Diesel	$0.88 - $1.62	$	1.13	$0.92 - $1.62	$	1.14
Historical Differential to PADD 5 Diesel	$1.91 - $3.05	$	2.31	$1.89 - $3.02	$	2.36

Convertible Promissory Note

In connection with the Company’s loan commitment to a certain equity method investee, the Company was issued a convertible promissory note with a principal balance equal to the amount of drawdown on the loan commitment (see Note 17). The convertible promissory note bears interest at 7% per annum, compounded quarterly, with a maturity date the earlier of May 7, 2024 or upon the occurrence of a triggering event such as change of control or an event of default. The convertible promissory note is classified as available-for-sale and is carried at fair value, which is measured using the income approach. Under the income approach, the Company used a DCF model in which cash flows anticipated over the term of the note are discounted to their present value using an expected discount rate. The discount rate used reflects the interest rates offered on loans of similar terms and to borrowers of similar credit quality, which are Level 3 inputs. As such, this valuation approach is considered a Level 3 fair value measurement.

The following table provides quantitative information about the significant inputs used to estimate the fair value of the convertible promissory note as of December 31, 2022 and June 30, 2023:



Significant Unobservable Inputs	December 31, 2022	June 30, 2023
Risk-free interest rate	4.57%	5.42%
Credit adjustment	8.36%	6.80%
Credit adjusted discount rate	12.93%	12.22%

The above significant unobservable inputs are subject to change based on changes in economic and market conditions. The use of significant unobservable inputs creates uncertainty in the measurement of fair value as of the reporting date. Significant increase or decrease in any of the inputs in isolation would result in a significantly lower or higher fair value measurement. Generally, a change in market interest rates is accompanied by a directionally opposite

change in the estimated fair value of fixed-rate debt securities. The Company records changes in the fair value of available-for-sale debt securities in “Unrealized gain (loss) on available-for-sale securities” within other comprehensive income (loss) in the accompanying condensed consolidated statements of comprehensive loss.

There were no transfers of assets or liabilities between Level 1, Level 2, or Level 3 of the fair value hierarchy as of December 31, 2022 or June 30, 2023.

The following tables provide information by level for assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2022 and June 30, 2023 (in thousands):


	December 31, 2022		Level 1		Level 2		Level 3
Assets:
Available-for-sale securities:
U.S. government securities ⁽¹⁾	$	64,880	$	64,880	$	—	$	—
Zero coupon bonds ⁽¹⁾		74,159		—		74,159		—
Convertible promissory note ⁽⁴⁾		1,880		—		—		1,880
Certificates of deposit ⁽¹⁾		530		—		530		—
Embedded derivatives ⁽³⁾		6,755		—		—		6,755
Liabilities:
Commodity swap contracts ⁽²⁾	$	3,845	$	—	$	—	$	3,845


	June 30, 2023		Level 1		Level 2		Level 3
Assets:
Available-for-sale securities:
U.S. government securities ⁽¹⁾	$	138,039	$	138,039	$	—	$	—
Convertible promissory note ⁽⁴⁾		4,295		—		—		4,295
Certificates of deposit ⁽¹⁾		530		—		530		—
Embedded derivatives ⁽³⁾		6,837		—		—		6,837
Liabilities:
Embedded derivatives ⁽³⁾		80		—		—		80
Commodity swap contracts ⁽²⁾	$	2,779	$	—	$	—	$	2,779

(1)	Included in “Short-term investments” in the accompanying condensed consolidated balance sheets. See Note 5 for more information.

(2)	Included in “Derivative liabilities, related party” and “Long-term portion of derivative liabilities, related party” as of December 31, 2022 and in “Derivative liabilities, related party” as of June 30, 2023 in the accompanying condensed consolidated balance sheets. See Note 6 for more information.

(3)

Included in “Prepaid expenses and other current assets” and “Notes receivable and other long-term assets, net” as of December 31, 2022 and in “Prepaid expenses and other current assets,” “Notes receivable and other long-term assets, net,” and “Accrued liabilities” as of June 30, 2023 in the accompanying condensed consolidated balance sheets. See Note 6 for more information.

(4)	Included in “Notes receivable and other long-term assets, net” as of December 31, 2022 and in “Other receivables” as of June 30, 2023 in the accompanying condensed consolidated balance sheets.

The following table provides a reconciliation of the beginning and ending balances of items measured at fair value on a recurring basis as shown in the tables above that used significant unobservable inputs (Level 3), as well as the change in unrealized gains or losses for the periods included in earnings or other comprehensive income (loss) (in thousands):


	Assets:		Assets:		Assets:		Liabilities:		Liabilities:
	Commodity		Embedded		Convertible		Commodity		Embedded
	Swap Contracts		Derivatives		Promissory Note		Swap Contracts		Derivatives
Balance as of March 31, 2022	$	—	$	9,923	$	—	$	(8,566)	$	—
Settlements, net		—		—		—		2,622		—
Total gain (loss)		—		1,422		—		(5,090)		(32)
Balance as of June 30, 2022	$	—	$	11,345	$	—	$	(11,034)	$	(32)

Balance as of March 31, 2023	$	—	$	4,949	$	3,048	$	(3,875)	$	(696)
Settlements, net		—		—		—		1,441		—
Total gain (loss)		—		1,888		889		(345)		616
Purchases		—		—		1,268		—		—
Equity method investment loss		—		—		(910)		—		—
Balance as of June 30, 2023	$	—	$	6,837	$	4,295	$	(2,779)	$	(80)

Change in unrealized gain (loss) for the three months ended June 30, 2022 included in earnings	$	—	$	1,422	$	—	$	(2,468)	$	(32)
Change in unrealized gain (loss) for the three months ended June 30, 2023 included in earnings	$	—	$	1,888	$	—	$	1,096	$	616
Change in unrealized gain (loss) for the three months ended June 30, 2023 included in other comprehensive income (loss)	$	—	$	—	$	889	$	—	$	—


	Assets:		Assets:		Assets:		Liabilities:		Liabilities:
	Commodity		Embedded		Convertible		Commodity		Embedded
	Swap Contracts		Derivatives		Promissory Note		Swap Contracts		Derivatives
Balance as of December 31, 2021	$	—	$	6,776	$	—	$	(4,383)	$	—
Settlements, net		—		—		—		3,901		—
Total gain (loss)		—		4,569		—		(10,552)		(32)
Balance as of June 30, 2022	$	—	$	11,345	$	—	$	(11,034)	$	(32)

Balance as of December 31, 2022	$	—	$	6,755	$	1,880	$	(3,845)	$	—
Settlements, net		(1,424)		—		—		2,456		—
Total gain (loss)		1,424		82		1,105		(1,390)		(80)
Purchases		—		—		2,478		—		—
Equity method investment loss		—		—		(1,168)		—		—
Balance as of June 30, 2023	$	—	$	6,837	$	4,295	$	(2,779)	$	(80)

Change in unrealized gain (loss) for the six months ended June 30, 2022 included in earnings	$	—	$	4,569	$	—	$	(6,651)	$	(32)
Change in unrealized gain (loss) for the six months ended June 30, 2023 included in earnings	$	—	$	82	$	—	$	1,066	$	(80)
Change in unrealized gain (loss) for the six months ended June 30, 2023 included in other comprehensive income (loss)	$	—	$	—	$	1,105	$	—	$	—

Other Financial Assets and Liabilities

The carrying amounts of the Company’s cash, cash equivalents, receivables and payables approximate fair value due to the short-term nature of those instruments. The carrying amounts of the Company’s debt instruments approximated their respective fair values as of December 31, 2022 and June 30, 2023. The fair values of these debt instruments were estimated using a DCF analysis based on interest rates offered on loans with similar terms to borrowers of similar credit quality, which are Level 3 inputs. See Note 12 for more information about the Company’s debt instruments.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Derivative Instruments and Hedging Activities - Summary of Commodity Derivative Activity (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Derivative Assets
Gross Amounts Recognized	$ 6,837	$ 6,755
Gross Amounts Offset	0	0
Net Amount Presented	6,837	6,755
Derivative Liability
Gross Amounts Recognized	2,859	3,845
Gross Amounts Offset	0	0
Net Amount Presented	2,859	3,845
Commodity swaps
Derivative Liability
Gross Amounts Recognized	2,779
Gross Amounts Offset	0
Net Amount Presented	$ 2,779
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Derivative Liability Current, Related Party
Fueling agreements
Derivative Liability
Gross Amounts Recognized	$ 80
Net Amount Presented	$ 80
Derivative Liability, Statement of Financial Position [Extensible Enumeration]	Accrued Liabilities, Current
Notes receivable and other long-term assets, net \| Fueling agreements
Derivative Assets
Gross Amounts Recognized	$ 4,538	5,115
Gross Amounts Offset	0	0
Net Amount Presented	4,538	5,115
Prepaid expenses and other current assets \| Fueling agreements
Derivative Assets
Gross Amounts Recognized	2,299	1,640
Gross Amounts Offset	0	0
Net Amount Presented	$ 2,299	1,640
Current portion of derivative liabilities, related party \| Commodity swaps
Derivative Assets
Gross Amounts Offset		0
Derivative Liability
Gross Amounts Recognized		2,415
Net Amount Presented		2,415
Long-term portion of derivative liabilities, related party \| Commodity swaps
Derivative Assets
Gross Amounts Offset		0
Derivative Liability
Gross Amounts Recognized		1,430
Net Amount Presented		$ 1,430

Net Income (Loss) Per Share

6 Months Ended

Jun. 30, 2023

Earnings Per Share [Abstract]

Net Income (Loss) Per Share

Note 13—Net Income (Loss) Per Share

Basic net income (loss) per share is computed by dividing the net income (loss) attributable to Clean Energy Fuels Corp. by the weighted-average number of common shares outstanding and common shares issuable for little or no cash consideration during the period. Diluted net income (loss) per share is computed by dividing the net income (loss) attributable to Clean Energy Fuels Corp. by the weighted-average number of common shares outstanding and common shares issuable for little or no cash consideration during the period and potentially dilutive securities outstanding during the period, and therefore reflects the dilution from common shares that may be issued upon exercise or conversion of these potentially dilutive securities, such as stock options, warrants, convertible notes and restricted stock units. The dilutive effect of stock options and warrants is computed under the treasury stock method. The dilutive effect of convertible notes and restricted stock units is computed under the if-converted method. Potentially dilutive securities are excluded from the computations of diluted net income (loss) per share if their effect would be antidilutive.

The following table sets forth the computations of basic and diluted earnings (loss) per share for the three and six months ended June 30, 2022 and 2023 (in thousands except share and per share amounts):


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Net loss attributable to Clean Energy Fuels Corp.	$	(13,235)	$	(16,301)	$	(37,426)	$	(54,998)

Weighted-average common shares outstanding		222,433,900		222,908,402		222,496,426		222,813,286
Dilutive effect of potential common shares from restricted stock units, stock options and stock warrants		—		—		—		—
Weighted-average common shares outstanding - diluted		222,433,900		222,908,402		222,496,426		222,813,286
Basic and diluted loss per share	$	(0.06)	$	(0.07)	$	(0.17)	$	(0.25)

The following potentially dilutive securities have been excluded from the diluted net loss per share calculations because their effect would have been antidilutive. Although these securities were antidilutive for these periods, they could be dilutive in future periods.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Stock options		16,410,764		18,154,864		16,410,764		18,154,864
Restricted stock units		680,191		367,145		680,191		367,145
Amazon warrant shares		58,767,714		58,767,714		58,767,714		58,767,714
Total		75,858,669		77,289,723		75,858,669		77,289,723

Revenue from Contracts with Customers

6 Months Ended

Jun. 30, 2023

Revenue from Contract with Customer [Abstract]

Revenue from Contracts with Customers

Note 2—Revenue from Contracts with Customers

Revenue Recognition Overview

The Company recognizes revenue when control of the promised goods or services is transferred to its customers, in an amount that reflects the consideration to which it expects to be entitled in exchange for the goods or services. To achieve that core principle, a five-step approach is applied: (1) identify the contract with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract, and (5) recognize revenue allocated to each performance obligation when the Company satisfies the performance obligation. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer, and is the unit of account for revenue recognition.


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Product revenue:
Volume-related
Fuel sales⁽¹⁾	$	67,094	$	53,267	$	125,712	$	160,162
Change in fair value of derivative instruments⁽²⁾		(1,079)		3,600		(2,114)		1,068
RIN Credits		9,795		5,377		17,727		9,880
LCFS Credits		4,085		2,474		7,519		4,772
AFTC ⁽³⁾		(9)		5,059		222		9,555
Total volume-related product revenue		79,886		69,777		149,066		185,437
Station construction sales		5,967		5,852		9,294		9,919
Total product revenue		85,853		75,629		158,360		195,356
Service revenue:
Volume-related, O&M services		11,035		13,913		21,745		25,957
Other services		336		1,006		616		1,418
Total service revenue		11,371		14,919		22,361		27,375
Total revenue	$	97,224	$	90,548	$	180,721	$	222,731

(1)

(2)

(3)	Represents the federal alternative fuel excise tax credit (“AFTC”). See Note 19 for more information.

Remaining Performance Obligations

Remaining performance obligations represent the transaction price of customer orders for which the work has not been performed. As of June 30, 2023, the aggregate amount of the transaction price allocated to remaining performance obligations was $28.5 million, which related to the Company’s station construction sale contracts. The Company expects to recognize revenue on the remaining performance obligations under these contracts over the next 12 to 24 months.

For volume-related revenue, the Company has elected to apply an optional exemption, which waives the requirement to disclose the remaining performance obligation for revenue recognized through the ‘right to invoice’ practical expedient.

Contract Balances

The timing of revenue recognition, billings and cash collections results in billed accounts receivable, unbilled receivables (contract assets), and customer advances and deposits (contract liabilities) in the accompanying condensed consolidated balance sheets.

As of December 31, 2022 and June 30, 2023, the Company’s contract balances were as follows (in thousands):


	December 31,		June 30,
	2022		2023
Accounts receivable, net	$	91,430	$	74,746

Contract assets - current	$	6,063	$	8,724
Contract assets - non-current		2,976		2,699
Contract assets - total	$	9,039	$	11,423

Contract liabilities - current	$	5,477	$	3,329
Contract liabilities - non-current		—		—
Contract liabilities - total	$	5,477	$	3,329

Accounts Receivable, Net

“Accounts receivable, net” in the accompanying condensed consolidated balance sheets includes billed and accrued amounts that are currently due from customers. The amounts due are stated at their net estimated realizable value. The Company maintains an allowance to provide for the estimated amount of receivables that will not be collected. The allowance is based on an assessment of customer creditworthiness, historical payment experience, the age of outstanding receivables, and economic conditions that may affect a customer’s ability to pay.

Contract Assets

Contract assets include unbilled amounts typically resulting from the Company’s station construction sale contracts, when the cost-to-cost method of revenue recognition is utilized and revenue recognized exceeds the amount billed to the customer, and right to payment is not just subject to the passage of time. Amounts may not exceed their net realizable value. Contract assets are classified as current or noncurrent based on the timing of billings. The current portion is included in “Other receivables” and in “Prepaid expenses and other current assets” and the noncurrent portion is included in “Notes receivable and other long-term assets, net” in the accompanying condensed consolidated balance sheets.

Contract Liabilities

Contract liabilities consist of billings in excess of revenue recognized from the Company’s station construction sale contracts and payments received primarily from customers of NG Advantage, LLC (“NG Advantage”) in advance of the satisfaction of performance obligations and are classified as current or noncurrent based on when the related revenue

is expected to be recognized. The current portion and noncurrent portion of contract liabilities are included in “Deferred revenue” and in “Other long-term liabilities,” respectively, in the accompanying condensed consolidated balance sheets.

Revenue recognized in the six months ended June 30, 2022 relating to the Company’s contract liability balances as of December 31, 2021 was $0.9 million. The decrease in the contract liability balance in the six months ended June 30, 2023 is primarily driven by $3.3 million of revenue recognized relating to the Company’s contract liability balance as of December 31, 2022, partially offset by billings in excess of revenue recognized in the six months ended June 30, 2023.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-10

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-15

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Revenue from Contracts with Customers - Contract Liabilities (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Revenue from Contract with Customer [Abstract]
Contract with customer, liability, revenue recognized	$ 3.3	$ 0.9

Fair Value Measurements - Fair Value Recognition - Assets (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Reconciliation of the beginning and ending balances of assets measured at fair value using significant unobservable inputs (Level 3)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income [Extensible List]		Revenue from Contract with Customer, Excluding Assessed Tax		Revenue from Contract with Customer, Excluding Assessed Tax
Commodity swap contracts
Reconciliation of the beginning and ending balances of assets measured at fair value using significant unobservable inputs (Level 3)
Settlements, net			$ (1,424)
Total gain (loss)			1,424
Embedded derivatives
Reconciliation of the beginning and ending balances of assets measured at fair value using significant unobservable inputs (Level 3)
Beginning balance	$ 4,949	$ 9,923	6,755	$ 6,776
Total gain (loss)	1,888	1,422	82	4,569
Ending balance	6,837	11,345	6,837	11,345
Change in unrealized gain (loss) included in earnings	1,888	$ 1,422	82	$ 4,569
Convertible promissory note
Reconciliation of the beginning and ending balances of assets measured at fair value using significant unobservable inputs (Level 3)
Beginning balance	3,048		1,880
Total gain (loss)	889		1,105
Purchases	1,268		2,478
Ending balance	4,295		4,295
Change in unrealized gain (loss) included in earnings	889		1,105
Equity method investment loss	$ (910)		$ (1,168)

Related Party Transactions (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jun. 28, 2023	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Advance given				$ 5,500	$ 0
Amount provided for funding in certain equity method investee		$ 1,200		2,300
Outstanding balance		144,875		144,875		$ 145,564
Convertible promissory note
Related Party Transaction [Line Items]
Outstanding balance		4,300		4,300		1,900
Related Party \| TOTALEnergies S.E.
Related Party Transaction [Line Items]
Proceeds from related party			$ 1,500	1,400	2,900
Receivables from related party						2,500
Related party expense		1,800	2,800	2,500	3,600
Payable to related parties						200
Related Party \| SAFE&CEC S.r.l.
Related Party Transaction [Line Items]
Proceeds from related party		100	100	300	100
Receivables from related party		100		100		300
Related party expense		6,200	1,600	9,200	5,700
Payable to related parties		4,300		4,300		3,300
Related Party \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Proceeds from related party		500	300	900	600
Related party expense		800	100	1,200	200
Related Party \| DR JV
Related Party Transaction [Line Items]
Advance given	$ 5,500
Receivables from related party		5,500		5,500
Related Party \| Management Fee for Services \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Receivables from related party		200		200		500
Related Party \| Business Expenses Reimbursement \| TotalEnergies JV and bpJV
Related Party Transaction [Line Items]
Receivables from related party		200		200		600
Other Equity Method Investees
Related Party Transaction [Line Items]
Proceeds from related party		200	$ 0	300	$ 0
Receivables from related party		$ 400		$ 400		$ 100

Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue from Contracts with Customers
Revenue	$ 90,548	$ 97,224	$ 222,731	$ 180,721
Contra revenue charge			27,652	8,533
Fuel Sales
Revenue from Contracts with Customers
Revenue	53,267	67,094	160,162	125,712
RIN Credits
Revenue from Contracts with Customers
Revenue	5,377	9,795	9,880	17,727
LCFS Credits
Revenue from Contracts with Customers
Revenue	2,474	4,085	4,772	7,519
AFTC
Revenue from Contracts with Customers
Revenue	5,059	(9)	9,555	222
Total volume-related product revenue
Revenue from Contracts with Customers
Revenue	69,777	79,886	185,437	149,066
Station construction sales
Revenue from Contracts with Customers
Revenue	5,852	5,967	9,919	9,294
Product revenue
Revenue from Contracts with Customers
Revenue	75,629	85,853	195,356	158,360
Volume-related, O&M services
Revenue from Contracts with Customers
Revenue	13,913	11,035	25,957	21,745
Other services
Revenue from Contracts with Customers
Revenue	1,006	336	1,418	616
Service revenue
Revenue from Contracts with Customers
Revenue	14,919	11,371	27,375	22,361
Volume-Related
Revenue from Contracts with Customers
Gain (loss) due to changes in fair value	3,600	(1,079)	1,068	(2,114)
Contra revenue charge	$ 13,900	$ 4,800	$ 27,700	$ 8,500

General

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

General

Note 1—General

Nature of Business

Clean Energy Fuels Corp., together with its majority and wholly owned subsidiaries (hereinafter collectively referred to as the “Company,” unless the context or the use of the term indicates or requires otherwise) is engaged in the business of selling renewable and conventional natural gas as alternative fuels for vehicle fleets and related fueling solutions to its customers, primarily in the United States and Canada. The Company’s principal business is supplying renewable natural gas (“RNG”) and conventional natural gas, in the form of compressed natural gas (“CNG”) and liquefied natural gas (“LNG”), for medium and heavy-duty vehicles and providing operation and maintenance (“O&M”) services to public and private vehicle fleet customer stations. The Company is also focused on developing, owning, and operating dairy and other livestock waste RNG projects and supplying RNG (currently procured solely from third party sources and will be supplemented by internally produced RNG when the Company’s RNG projects come online) to its customers in the heavy and medium-duty commercial transportation sector.

As a comprehensive clean energy solution provider, the Company also designs and builds, as well as operates and maintains, public and private vehicle fueling stations in the United States and Canada; sells and services compressors and other equipment used in RNG production and at fueling stations; transports and sells RNG and conventional natural gas, in the form of CNG and LNG, via “virtual” natural gas pipelines and interconnects; sells U.S. federal, state and local government credits it generates by selling RNG in the form of CNG and LNG as a vehicle fuel, including Renewable Identification Numbers (“RIN Credits” or “RINs”) under the federal Renewable Fuel Standard Phase 2 and credits under the California and the Oregon Low Carbon Fuel Standards (collectively, “LCFS Credits”); and obtains federal, state and local tax credits, grants and incentives.

Basis of Presentation

The accompanying interim unaudited condensed consolidated financial statements include the accounts of the Company and its subsidiaries, and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s consolidated financial position as of June 30, 2023, results of operations, comprehensive loss, and stockholders’ equity for the three and six months ended June 30, 2022 and 2023, and cash flows for the six months ended June 30, 2022 and 2023. All intercompany accounts and transactions have been eliminated in consolidation. The results of operations for the three and six months ended June 30, 2022 and 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023 or for any other interim period or any future year.

Certain information and disclosures normally included in the notes to consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”), but the resultant disclosures contained herein are in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) as they apply to interim reporting. The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2022 that are included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2023.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying condensed consolidated financial statements and these notes. Actual results could differ from those estimates and may result in

material effects on the Company’s operating results and financial position. Significant estimates made in preparing the accompanying condensed consolidated financial statements include (but are not limited to) those related to revenue recognition, fair value measurements, goodwill and long-lived asset valuations and impairment assessments, income tax valuations, stock-based compensation expense and stock-based sales incentive charges.

Amazon Warrant

The Amazon Warrant (defined in Note 14) is accounted for as an equity instrument and measured in accordance with Accounting Standards Codification (“ASC”) 718, Compensation – Stock Compensation. This instrument is classified in the condensed consolidated statements of operations in accordance with ASC 606, Revenue from Contracts with Customers, which states that for awards granted to a customer that are not in exchange for distinct goods or services, the fair value of the awards earned based on service or performance conditions is recorded as a reduction of the transaction price. To determine the fair value of the Amazon Warrant in accordance with ASC 718, the Company used the Black-Scholes option pricing model, which is based in part on assumptions that require management to use judgment. Based on the fair value of the award, the Company determines the amount of non-cash stock-based sales incentive charges on the customer’s pro-rata achievement of vesting conditions, which is recorded as a reduction of revenue in the condensed consolidated statements of operations. See Note 14 for additional information.

Tourmaline Joint Development

In April 2023, the Company and Tourmaline Oil Corp. (“Tourmaline”) announced a CAD $70 million Joint Development Agreement to build and operate a network of CNG stations along key highway corridors across Western Canada. Under a 50-50 shared investment, the Company and Tourmaline expect to construct and commission up to 20 CNG fueling stations over the next five years, allowing heavy-duty trucks and other commercial transportation fleets that operate in the area to transition to the use of CNG, a lower carbon alternative to gasoline and diesel. Costs associated with station construction and profit and loss arising from station operation are shared 50-50 between the Company and Tourmaline. This arrangement between the Company and Tourmaline to jointly develop, build and operate CNG fueling stations is accounted for in accordance with ASC 808, Collaborative Arrangements, which states that (1) costs incurred and revenue generated from transactions with third parties be separately recorded by each participant in its own financial statements, (2) the participant who is deemed to be the principal for a given transaction under ASC 606, Revenue from Contracts with Customers, will record the transaction on a gross basis in its financial statements, and (3) payments between participants that are within the scope of other authoritative accounting literature on income statement classification shall be accounted for using the relevant provisions of that literature. If the payments are not within the scope of other authoritative accounting literature, then the income statement classification for the payments shall be based on an analogy to authoritative accounting literature or if there is no appropriate analogy, a reasonable, rational, and consistently applied accounting policy election.

The Company determined that it is the principal for the revenue generated from third parties under this collaborative arrangement with Tourmaline in accordance with ASC 606; as such, the associated revenue and cost of sales generated and incurred are recognized on a gross basis in the condensed consolidated statements of operations. Net participation of profit and loss owed to or from Tourmaline is recorded as an increase or decrease to cost of sales, respectively, as the transaction is not deemed to be with a customer within the scope of ASC 606. Capitalized station costs are presented at half of the total development and construction costs in the condensed consolidated balance sheets, corresponding to the Company’s 50% ownership in the shared assets.

Recently Issued Accounting Pronouncements

In March 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-01, Leases (Topic 842): Common Control Arrangements. This ASU permits private entities with common control arrangements that may contain or be leases to use any written terms and conditions between the parties, without regard to their legal enforceability, to identify, classify and account for common control leases. In addition, all lessees (public or private), in general, amortize leasehold improvements related to a common control lease over their useful life to the common control group, regardless of the ASC 842 lease term, as long as they continue to control the use of the underlying leased asset. The ASU is effective for fiscal years, including interim periods within those years, beginning after

December 15, 2023, with early adoption allowed. The Company is currently evaluating the impact of adopting this new ASU and does not expect the adoption to have a material effect on the Company’s condensed consolidated financial statements.

Investments in Other Entities and Noncontrolling Interest in a Subsidiary - SAFE&CEC S.r.l (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Dec. 29, 2017
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments	$ (1,915)	$ (1,193)	$ (3,805)	$ (2,870)
SAFE&CEC S.r.l.
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)						49.00%
Income (loss) from equity method investments	200	$ (100)	(300)	$ (200)
Investment balance	$ 22,200		$ 22,200		$ 21,800
SAFE&CEC S.r.l. \| Landi Renzo S.p.A.
Schedule of Equity Method Investments [Line Items]
Ownership interest (as a percent)						51.00%

Related Party Transactions

6 Months Ended

Jun. 30, 2023

Related Party Transactions

Note 20—Related Party Transactions

TotalEnergies S.E.

In the three and six months ended June 30, 2022, the Company recognized revenue of $1.5 million and $2.9 million, respectively, relating to equipment lease revenue and LNG sold to TotalEnergies and its affiliates in the ordinary course of business. In the six months ended June 30, 2023, the Company recognized revenue of $1.4 million relating to RINs and LNG sold to TotalEnergies and its affiliates in the ordinary course of business, equipment lease revenue, AFTCs, and settlements on commodity swap contracts (Note 6). Revenue recognized in the three months ended June 30, 2023 was immaterial. As of December 31, 2022, the Company had receivables from TotalEnergies of $2.5 million. Outstanding receivables due from TotalEnergies were immaterial as of June 30, 2023.

In the three and six months ended June 30, 2022, the Company paid TotalEnergies $2.8 million and $3.6 million, respectively, for expenses incurred in the ordinary course of business, settlements on commodity swap contracts (Note 6), and the guaranty fee under the Credit Support Agreement with TotalEnergies Holdings USA Inc., a wholly owned subsidiary of TotalEnergies. In the three and six months ended June 30, 2023, the Company paid TotalEnergies $1.8 million and $2.5 million, respectively, for expenses incurred in the ordinary course of business and for settlements on commodity swap contracts (Note 6). As of December 31, 2022, total payables due to TotalEnergies was $0.2 million. Total payables due to TotalEnergies were immaterial as of June 30, 2023.

SAFE&CEC S.r.l.

In the three and six months ended June 30, 2022, the Company received $0.1 million and $0.1 million, respectively, from SAFE&CEC S.r.l. in the ordinary course of business. In the three and six months ended June 30, 2023, the Company received $0.1 million and $0.3 million, respectively, from SAFE&CEC S.r.l. in the ordinary course of business. As of December 31, 2022 and June 30, 2023, the Company had receivables due from SAFE&CEC S.r.l. of $0.3 million and $0.1 million, respectively.

In the three and six months ended June 30, 2022, the Company paid SAFE&CEC S.r.l. $1.6 million and $5.7 million, respectively, for parts and equipment in the ordinary course of business. In the three and six months ended June 30, 2023, the Company paid SAFE&CEC S.r.l. $6.2 million and $9.2 million, respectively, for parts and equipment in the ordinary course of business. As of December 31, 2022 and June 30, 2023, the Company had payables due to SAFE&CEC S.r.l. of $3.3 million and $4.3 million, respectively.

TotalEnergies Joint Venture(s) and bpJV

Pursuant to the TotalEnergies JV Agreement and the bp JV Agreement, the Company manages the day-to-day operations of RNG projects under the joint ventures in exchange for management fees. In the three and six months ended June 30, 2022, the Company recognized management fee revenue of $0.3 million and $0.6 million, respectively. In the three and six months ended June 30, 2023, the Company recognized management fee revenue of $0.5 million and $0.9 million, respectively. As of December 31, 2022 and June 30, 2023, the Company had management fees receivable due from the joint ventures with TotalEnergies and bp of $0.5 million and $0.2 million, respectively.

In the three and six months ended June 30, 2022, the Company paid $0.1 million and $0.2 million, respectively, on behalf of the joint ventures for costs incurred in the ordinary course of business. In the three and six months ended June 30, 2023, the Company paid $0.8 million and $1.2 million, respectively, on behalf of the joint ventures for costs incurred in the ordinary course of business. As of December 31, 2022 and June 30, 2023, the Company had receivables due from

the joint ventures with TotalEnergies and bp of $0.6 million and $0.2 million, respectively, representing outstanding unreimbursed costs that the Company paid on behalf of the joint ventures.

In connection with the capital call issued by the DR JV on June 28, 2023, the Company advanced $5.5 million to the DR JV. Proceeds from the advance were used to fund required loan reserves and to paydown outstanding liabilities of the DR JV (see Note 3). As of June 30, 2023, the Company had a receivable due from the DR JV of $5.5 million, which is expected to be paid by the DR JV before the end of 2023.

Other Equity Method Investees

Pursuant to the Note Purchase Agreement, in the three and six months ended June 30, 2023, the Company provided $1.2 million and $2.3 million, respectively, to a certain equity method investee in connection with the loan commitment (see Note 17). As of December 31, 2022 and June 30, 2023, the carrying amount of the Company’s convertible promissory note measured at fair value was $1.9 million and $4.3 million, respectively, and is included in “Notes receivable and other long-term assets, net” as of December 31, 2022 and in “Other receivables” as of June 30, 2023 in the accompanying condensed consolidated balance sheets.

In the three and six months ended June 30, 2023, the Company recognized management fee revenue of $0.2 million and $0.3 million, respectively, relating to other equity method investees. No management fee revenue was recognized in the three and six months ended June 30, 2022. As of December 31, 2022 and June 30, 2023, the Company had management fees receivable due from other equity method investees of $0.1 million and $0.4 million, respectively.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

+ Details

Fair Value Measurements - Convertible Promissory Note (Details) - USD ($)	Jun. 30, 2023	Dec. 31, 2022	Nov. 07, 2022
Fair Value Measurements
Interest rate			7.00%
Convertible promissory note
Fair Value Measurements
Interest rate	7.00%
Convertible promissory note \| Risk-free interest rate
Fair Value Measurements
Debt instrument, measurement input	$ 5.42	$ 4.57
Convertible promissory note \| Credit adjustment
Fair Value Measurements
Debt instrument, measurement input	6.80	8.36
Convertible promissory note \| Credit adjusted discount rate
Fair Value Measurements
Debt instrument, measurement input	$ 12.22	$ 12.93

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities:
Net loss	$ (55,318)	$ (37,938)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	21,571	21,946
Provision for credit losses and inventory	1,006	1,006
Stock-based compensation expense	12,189	14,721
Stock-based sales incentive charges	27,652	8,533
Change in fair value of derivative instruments	(1,068)	2,114
Amortization of discount and debt issuance cost	(2,190)	(306)
Gain on disposal of property and equipment	(101)	(66)
Loss on extinguishment of debt	0	2,268
Asset impairments and other charges	482	0
Loss from equity method investments	3,805	2,870
Non-cash lease expense	2,919	1,687
Deferred income taxes	(165)	62
Changes in operating assets and liabilities:
Accounts and other receivables	16,518	19,024
Inventory	(3,489)	(4,487)
Prepaid expenses and other assets	(6,956)	(2,002)
Operating lease liabilities	(2,075)	(1,747)
Accounts payable	(6,351)	6,912
Deferred revenue	(1,050)	(1,034)
Accrued liabilities and other	(14,341)	(1,325)
Net cash provided by (used in) operating activities	(6,962)	32,238
Cash flows from investing activities:
Purchases of short-term investments	(186,273)	(194,353)
Maturities and sales of short-term investments	190,500	194,250
Purchases of and deposits on property and equipment	(42,754)	(17,447)
Grant proceeds for capital projects	1,947	0
Disbursements for loans receivable	(2,340)	(516)
Proceeds from paydowns, maturities, and sales of loans receivables	1,612	218
Cash received from sale of certain assets of subsidiary, net	0	3,885
Investments in other entities	(5,500)	(51,600)
Payment and deposits on equipment and manure rights for RNG production projects	(15,080)	(4,915)
Proceeds received for joint development and construction of station projects	1,172	0
Advance to DR JV	(5,500)	0
Proceeds from disposal of property and equipment	198	80
Net cash (used in) investing activities	(62,018)	(70,398)
Cash flows from financing activities:
Issuance of common stock	335	573
Repurchase of common stock	0	(6,122)
Payments of tax withholdings on net settlement of equity awards	(175)	0
Fees paid for lender and debt issuance costs	(1,440)	(50)
Proceeds for Adopt-a-Port program	150	890
Repayment of proceeds for Adopt-a-Port program	(705)	(525)
Proceeds from debt instruments	255	14,000
Repayments of debt instruments and finance lease obligations	(612)	(17,315)
Payments of debt extinguishment costs	0	(2,186)
Net cash (used in) financing activities	(2,192)	(10,735)
Effect of exchange rates on cash, cash equivalents and restricted cash	384	(66)
Net (decrease) in cash, cash equivalents and restricted cash	(70,788)	(48,961)
Cash, cash equivalents and restricted cash, beginning of period	125,950	106,456
Cash, cash equivalents and restricted cash, end of period	55,162	57,495
Supplemental disclosure of cash flow information:
Income taxes paid	57	50
Interest paid, net of $0 and $581 capitalized, respectively	$ 8,279	$ 923

Condensed Consolidated Statements of Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Foreign currency translation adjustment, tax	$ 0	$ 0	$ 0	$ 0
Unrealized gains on available-for sale securities, tax	$ 0	$ 0	$ 0	$ 0

Investments in Other Entities and Noncontrolling Interest in a Subsidiary - bp Joint Venture (Details) - USD ($) $ in Thousands, shares in Millions			1 Months Ended			3 Months Ended		6 Months Ended
	Jun. 21, 2021	Apr. 13, 2021	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Mar. 31, 2022	Dec. 18, 2020
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments						$ (1,915)	$ (1,193)	$ (3,805)	$ (2,870)
BP Products North America \| bp Loan
Schedule of Equity Method Investments [Line Items]
Debt issuance amount												$ 50,000
bpJV \| ADG RNG Production Facilities
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture	$ 50,200	$ 30,000
Additional commitment in joint venture		$ 20,000
Initial contribution commitment	30,000
Ownership interest (as a percent)						50.00%		50.00%
Income (loss) from equity method investments						$ (200)	$ (800)	$ (600)	$ (2,000)
Investment balance						$ 156,200		$ 156,200		$ 156,800
bpJV \| ADG RNG Production Facilities \| bpJV Capital Call
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture					$ 71,600
Initial contribution commitment			$ 38,100	$ 51,600	20,000
Capital call contribution amount					143,200
bpJV \| ADG RNG Production Facilities \| bpJV Capital Call 2
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture											$ 38,100
Capital call contribution amount											76,200
bpJV \| ADG RNG Production Facilities \| Class A Units
Schedule of Equity Method Investments [Line Items]
Number of units received		30.0
Payments to acquire units in joint venture	20,000
Priority Return to acquire additional units	$ 200
bpJV \| ADG RNG Production Facilities \| bp
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture		$ 50,000
bpJV \| ADG RNG Production Facilities \| bp \| bpJV Capital Call
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture					$ 71,600
bpJV \| ADG RNG Production Facilities \| bp \| bpJV Capital Call 2
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture											$ 38,100
bpJV \| ADG RNG Production Facilities \| bp \| Class A Units
Schedule of Equity Method Investments [Line Items]
Number of units received		30.0
bpJV \| ADG RNG Production Facilities \| bp \| Class B Units
Schedule of Equity Method Investments [Line Items]
Number of units received		20.0

Inventory

6 Months Ended

Jun. 30, 2023

Inventory Disclosure [Abstract]

Inventory

Note 9—Inventory

Inventory consists of raw materials and spare parts, work in process and finished goods and is stated at the lower of cost (first-in, first-out) or net realizable value. The Company evaluates inventory balances for excess quantities and obsolescence by analyzing estimated demand, inventory on hand, sales levels and other information and reduces inventory balances to net realizable value for excess and obsolete inventory based on this analysis.

Inventory as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Raw materials and spare parts	$	37,144	$	38,517
Total inventory	$	37,144	$	38,517

Alternative Fuel Excise Tax Credit (Details)	Jan. 01, 2022 $ / gal
Alternative Fuel Excise Tax Credit
Federal alternative fuels tax credit - CNG (in dollars per gasoline gallon equivalent)	0.50
Federal alternative fuels tax credit - LNG (in dollars per liquid gallon)	0.50

Stockholders' Equity - Authorized Shares (Details) - shares	Jun. 30, 2023	Dec. 31, 2022	Jun. 14, 2021	Jun. 13, 2021
Stockholders' Equity Note [Abstract]
Authorized shares (in shares)	455,000,000		454,000,000	304,000,000
Common stock, authorized (in shares)	454,000,000	454,000,000
Preferred stock, authorized (in shares)	1,000,000	1,000,000

Leases - Maturities of Lease Receivables (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Fiscal year:
Remainder of 2023	$ 481
2024	962
2025	962
2026	985
2027	1,105
Thereafter	1,218
Total minimum lease payments	5,713
Less amount representing interest	(1,260)
Present value of lease receivables	$ 4,453

Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022	Jun. 30, 2022	Dec. 31, 2021
Restricted Cash
Cash and cash equivalents	$ 53,150	$ 123,950
Restricted cash	2,000
Total cash, cash equivalents and restricted cash	55,162	125,950	$ 57,495	$ 106,456
Amount in excess of FDIC and CDIC limits	54,000	124,800
Standby letters of credit
Restricted Cash
Restricted cash	2,012	2,000
Held as collateral
Restricted Cash
Restricted cash	$ 2,000	$ 2,000

Net Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Net loss attributable to Clean Energy Fuels Corp.	$ (16,301)	$ (13,235)	$ (54,998)	$ (37,426)
Weighted-average common shares outstanding	222,908,402	222,433,900	222,813,286	222,496,426
Dilutive effect of potential common shares from restricted stock units and stock options	0	0	0	0
Weighted-average common shares outstanding - diluted	222,908,402	222,433,900	222,813,286	222,496,426
Basic loss per share (in dollars per share)	$ (0.07)	$ (0.06)	$ (0.25)	$ (0.17)
Diluted loss per share (in dollars per share)	$ (0.07)	$ (0.06)	$ (0.25)	$ (0.17)

- Definition

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

Derivative Instruments and Hedging Activities - Schedule of Weighted-Average Price of Open Commodity Swap Contracts (Details) - Not Designated as Hedging Instrument	6 Months Ended	12 Months Ended
	Jun. 30, 2023 $ / gal gal	Dec. 31, 2022 $ / gal gal
Commodity Swap 2023
Derivative [Line Items]
Volumes (Diesel Gallons) \| gal	2,500,000	5,000,000
Weighted-Average Price per Diesel Gallon (in usd per gallon) \| $ / gal	3.18	3.18
Commodity Swap 2024
Derivative [Line Items]
Volumes (Diesel Gallons) \| gal	1,875,000	1,875,000
Weighted-Average Price per Diesel Gallon (in usd per gallon) \| $ / gal	3.18	3.18

Debt (Tables)

6 Months Ended

Jun. 30, 2023

Debt Disclosure [Abstract]

Schedule of long-term debt

Debt obligations as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31, 2022
			Unamortized Debt		Balance, Net of
	Principal Balance		Financing Costs		Financing Costs
Riverstone term loan	$	150,000	$	4,529	$	145,471
Other debt		93		—		93
Total debt		150,093		4,529		145,564
Less amounts due within one year		(93)		—		(93)
Total long-term debt	$	150,000	$	4,529	$	145,471


	June 30, 2023
			Unamortized Debt		Balance, Net of
	Principal Balance		Financing Costs		Financing Costs
Riverstone term loan	$	150,000	$	5,380	$	144,620
Other debt		255		—		255
Total debt		150,255		5,380		144,875
Less amounts due within one year		(38)		—		(38)
Total long-term debt	$	150,217	$	5,380	$	144,837

Commitments and Contingencies - Long-Term Take-or-Pay Natural Gas Purchase Contracts (Details) - USD ($) $ in Millions	Jun. 30, 2023	Nov. 07, 2022
Fixed commitments under the contract payable in future
Interest rate		7.00%
Loan Commitment to an Equity Method Investee
Fixed commitments under the contract payable in future
Irrevocably committed amount		$ 5.5
Convertible promissory note
Fixed commitments under the contract payable in future
Interest rate	7.00%
Natural Gas Supply Agreement \| DGS
Fixed commitments under the contract payable in future
2023	$ 1.7
2024	$ 2.0

Stock-Based Compensation

6 Months Ended

Jun. 30, 2023

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

Note 14—Stock-Based Compensation


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Stock-based compensation expense, net of $0 tax in 2022 and 2023	$	6,468	$	6,093	$	14,721	$	12,189

As of June 30, 2023, there was $23.0 million of total unrecognized compensation costs related to unvested shares subject to outstanding service-based and market-based stock options and service-based restricted stock units. Unrecognized compensation costs associated with these stock-based awards are expected to be expensed over a weighted-average period of approximately 1.5 years. As of June 30, 2023, total unrecognized compensation costs related to unvested shares subject to outstanding performance-based stock options were $4.2 million.

Amazon Warrant

On April 16, 2021, the Company entered into a Project Addendum to Fuel Pricing Agreement (the “Fuel Agreement”) with Amazon Logistics, Inc., a subsidiary of Amazon.com, Inc. (“Amazon”), and a Transaction Agreement with Amazon (the “Transaction Agreement”), pursuant to which, among other things, the Company issued to Amazon.com NV Investment Holdings LLC, a subsidiary of Amazon (“Amazon Holdings”), a warrant to purchase up to an aggregate of 53,141,755 shares (the “Warrant Shares”) of the Company’s common stock at an exercise price of $13.49 per share. As a result of the issuance of additional shares of common stock under the Company’s at-the-market offering programs in 2021 and in accordance with the terms of the warrant, on June 14, 2021, the number of shares of the Company’s common stock that may be purchased pursuant to the warrant, at an exercise price of $13.49 per share, increased by an aggregate of 5,625,959 shares (the “Additional Warrant Shares”).

The Warrant Shares and the Additional Warrant Shares shall vest in multiple tranches, certain of which vested immediately upon execution of the Fuel Agreement. Subsequent tranches will vest over time based on fuel purchases by Amazon and its affiliates, up to a total of $500.0 million, excluding any payments attributable to “Pass Through Costs,” which consist of all costs associated with the delivered cost of gas and applicable taxes determined by reference to the selling price of gallons or gas sold. The right to exercise the warrants and to receive the Warrant Shares and Additional Warrant Shares (the “Amazon Warrant”) that have vested expires on April 16, 2031.

Non-cash stock-based sales incentive contra-revenue charges (“Amazon Warrant Charges”) associated with the Amazon Warrant are recognized as Amazon and its affiliates purchase fuel and vesting conditions become probable of being achieved, based on the grant date fair value of the Amazon Warrant.

The following table summarizes the Amazon Warrant activity for the six months ended June 30, 2023:


		Warrant
		Shares
Outstanding and unvested as of December 31, 2022		42,314,667
Granted		—
Vested		(1,763,112)
Outstanding and unvested as of June 30, 2023		40,551,555

1,763,112 shares of the Amazon Warrant vested in the six months ended June 30, 2023 based on fuel purchases made by Amazon and its affiliates. The Company recognized Amazon Warrant Charges of $4.8 million and $13.9 million in the three months ended June 30, 2022 and 2023, respectively, and $8.5 million and $27.7 million in the six months ended June 30, 2022 and 2023, respectively, relating to customer fuel purchases. As of December 31, 2022 and June 30,

2023, the Company had a customer incentive asset of $22.2 million and $10.6 million, respectively, classified in “Prepaid expenses and other current assets” in the accompanying condensed consolidated balance sheets.

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ (16,301)	$ (13,235)	$ (54,998)	$ (37,426)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Investments in Other Entities and Noncontrolling Interest in a Subsidiary

6 Months Ended

Jun. 30, 2023

Investments, All Other Investments [Abstract]

Investments in Other Entities and Noncontrolling Interest in a Subsidiary

Note 3— Investments in Other Entities and Noncontrolling Interest in a Subsidiary

TotalEnergies Joint Venture

On March 3, 2021, the Company entered into an agreement (the “TotalEnergies JV Agreement”) with TotalEnergies S.E. (“TotalEnergies”) to create 50/50 joint ventures to develop anaerobic digester gas (“ADG”) RNG production facilities in the United States. Pursuant to the TotalEnergies JV Agreement, each ADG RNG production facility project will be formed as a separate limited liability company (“LLC”) that is owned 50/50 by the Company and TotalEnergies, and contributions to such LLCs count toward the TotalEnergies JV Equity Obligations (as defined below). The TotalEnergies JV Agreement contemplates investing up to $400.0 million of equity in production projects, and TotalEnergies and the Company each committed to initially provide $50.0 million (the “TotalEnergies JV Equity Obligations”). In October 2021, TotalEnergies and the Company executed a LLC agreement (the “DR Development Agreement”) for an ADG RNG production facility project (the “DR JV”). Under the DR Development Agreement, TotalEnergies and the Company have each committed to contribute $7.0 million to the DR JV, and in November 2021, TotalEnergies and the Company each contributed an initial $4.8 million to the DR JV. On June 28, 2023, the DR JV issued a capital call for $11.0 million in additional funding, requiring TotalEnergies and the Company each to contribute $5.5 million. Funds from the capital call will be used to fund required loan reserves and to paydown outstanding liabilities of the DR JV. On June 30, 2023, the Company contributed $5.5 million and advanced $5.5 million to the DR JV. The $5.5 million advance is expected to be refunded to the Company by the DR JV before the end of 2023.

The Company accounts for its interest in the LLC using the equity method of accounting because the Company does not control but has the ability to exercise significant influence over the LLC’s operations. The Company recorded a loss of $0.1 million and $1.0 million from the LLC’s operations in the three months ended June 30, 2022 and 2023, respectively, and a loss of $0.1 million and $1.4 million from the LLC’s operations in the six months ended June 30, 2022 and 2023, respectively. The Company had an investment balance of $4.5 million and $8.6 million as of December 31, 2022 and June 30, 2023, respectively.

bp Joint Venture

On April 13, 2021, the Company entered into an agreement (the “bp JV Agreement”) with bp Products North America, Inc. (“bp”) that created a 50/50 joint venture (the “bpJV”) to develop, own and operate new ADG RNG production facilities in the United States. Pursuant to the bp JV Agreement, bp and the Company committed to provide $50.0 million and $30.0 million, respectively, with bp and the Company each receiving 30.0 million of Class A Units in the bpJV and bp also receiving 20.0 million of Class B Units in the bpJV. bp’s initial $50.0 million contribution was made on April 13, 2021 and consisted of all unpaid principal outstanding under the loan agreement dated December 18, 2020, pursuant to which bp advanced $50.0 million to the Company to fund capital costs and expenses incurred prior to formation of the bpJV, including capital costs and expenses for permitting, engineering, equipment, leases and feed stock rights.

Pursuant to the bp JV Agreement, the Company had the option, exercisable prior to August 31, 2021 (the “bp Option”), to commit an additional $20.0 million to the bpJV upon which bp’s Class B Units would convert into Class A Units. On June 21, 2021, the Company contributed $50.2 million to the bpJV, which consisted of (i) its initial contribution commitment of $30.0 million, (ii) the $20.0 million additional contribution to effect the conversion of bp’s Class B Units into Class A Units pursuant to the Company’s exercise of the bp Option, and (iii) $0.2 million for interest in accordance with the bp JV Agreement to effect the conversion of bp’s Class B Units into Class A Units.

In December 2021, the bpJV issued a capital call for $143.2 million in additional funding, requiring bp and the Company each to contribute $71.6 million, and, in March 2022, the bpJV issued a second capital call for $76.2 million in additional funding, requiring bp and the Company each to contribute $38.1 million. Pursuant to the bpJV capital calls, the Company contributed $20.0 million, $51.6 million and $38.1 million in December 2021, June 2022 and September 2022, respectively, satisfying in full the Company’s contribution obligations under these capital calls. As of June 30, 2023, bp and the Company each own 50% of the bpJV. 100% of the RNG produced from the projects developed and owned by the bpJV will be available to the Company pursuant to the Company’s marketing agreement with bp.

The Company accounts for its interest in the bpJV using the equity method of accounting because the Company does not control but has the ability to exercise significant influence over the bpJV’s operations. The Company recorded a loss of $0.8 million and $0.2 million from this investment in the three months ended June 30, 2022 and 2023, respectively, and a loss of $2.0 million and $0.6 million from this investment in the six months ended June 30, 2022 and 2023, respectively. The Company had an investment balance in the bpJV of $156.8 million and $156.2 million as of December 31, 2022 and June 30, 2023, respectively.

SAFE&CEC S.r.l.

On November 26, 2017, the Company, through its former subsidiary, IMW Industries Ltd. (formerly known as Clean Energy Compression Corp.) (“CEC”), entered into an investment agreement with Landi Renzo S.p.A. (“LR”), an alternative fuels company based in Italy. Pursuant to the investment agreement, the Company and LR agreed to combine their respective natural gas compressor fueling systems manufacturing subsidiaries, CEC and SAFE S.p.A, into a new company, SAFE&CEC S.r.l. (such combination transaction is referred to as the “CEC Combination”). SAFE&CEC S.r.l. is focused on manufacturing, selling and servicing natural gas fueling compressors and related equipment for the global natural gas fueling market. At the closing of the CEC Combination on December 29, 2017, the Company owned 49% of SAFE&CEC S.r.l., and LR owned 51% of SAFE&CEC S.r.l.

The Company accounts for its interest in SAFE&CEC S.r.l. using the equity method of accounting because the Company does not control but has the ability to exercise significant influence over SAFE&CEC S.r.l.’s operations. The Company recorded a loss of $0.1 million and a gain of $0.2 million in the three months ended June 30, 2022 and 2023, respectively, and a loss of $0.2 million and $0.3 million in the six months ended June 30, 2022 and 2023, respectively. The Company had an investment balance in SAFE&CEC S.r.l. of $21.8 million and $22.2 million as of December 31, 2022 and June 30, 2023, respectively.

NG Advantage

On October 14, 2014, the Company entered into a Common Unit Purchase Agreement (“UPA”) with NG Advantage for a 53.3% controlling interest in NG Advantage. Subsequently, the Company’s controlling interest increased in connection with various equity and financing arrangements with NG Advantage. As of June 30, 2023, the Company’s controlling interest in NG Advantage was 93.3%. NG Advantage is engaged in the business of transporting CNG in high-capacity trailers to industrial and institutional energy users, such as hospitals, food processors, manufacturers and paper mills that do not have direct access to natural gas pipelines.

The Company recorded a loss attributable to the noncontrolling interest in NG Advantage of $0.1 million and $0.2 million in the three months ended June 30, 2022 and 2023, respectively, and a loss attributable to the noncontrolling interest in NG Advantage of $0.5 million and $0.3 million in the six months ended June 30, 2022 and 2023, respectively. The value of the noncontrolling interest was $7.5 million and $7.2 million as of December 31, 2022 and June 30, 2023, respectively.

Investments in Equity Securities

For investments in equity securities of privately held entities without readily determinable fair values, the Company measures such investments at cost, adjusted for impairment, if any, and observable price changes in orderly transactions for the identical or similar investment of the same issuer. As of December 31, 2022 and June 30, 2023, the

Company had an investment balance recorded at cost of $8.0 million. The Company did not recognize any adjustments to the recorded cost basis in the three and six months ended June 30, 2022 and 2023.

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Revenue:
Total revenue	$ 90,548	$ 97,224	$ 222,731	$ 180,721
Cost of sales (exclusive of depreciation and amortization shown separately below):
Selling, general and administrative	28,548	26,481	58,197	54,408
Depreciation and amortization	10,893	10,556	21,571	21,946
Total operating expenses	103,603	109,097	271,198	212,651
Operating loss	(13,055)	(11,873)	(48,467)	(31,930)
Interest expense	(4,365)	(732)	(8,719)	(3,809)
Interest income	2,766	490	5,483	754
Other income, net	28	14	71	34
Loss from equity method investments	(1,915)	(1,193)	(3,805)	(2,870)
Loss before income taxes	(16,541)	(13,294)	(55,437)	(37,821)
Income tax (expense) benefit	55	(68)	119	(117)
Net loss	(16,486)	(13,362)	(55,318)	(37,938)
Loss attributable to noncontrolling interest	185	127	320	512
Net loss attributable to Clean Energy Fuels Corp.	$ (16,301)	$ (13,235)	$ (54,998)	$ (37,426)
Net loss attributable to Clean Energy Fuels Corp. per share:
Basic (in dollars per share)	$ (0.07)	$ (0.06)	$ (0.25)	$ (0.17)
Diluted (in dollars per share)	$ (0.07)	$ (0.06)	$ (0.25)	$ (0.17)
Weighted-average common shares outstanding:
Basic (in shares)	222,908,402	222,433,900	222,813,286	222,496,426
Diluted (in shares)	222,908,402	222,433,900	222,813,286	222,496,426
Product revenue
Revenue:
Total revenue	$ 75,629	$ 85,853	$ 195,356	$ 158,360
Cost of sales (exclusive of depreciation and amortization shown separately below):
Cost of sales	55,570	65,933	175,228	123,548
Service revenue
Revenue:
Total revenue	14,919	11,371	27,375	22,361
Cost of sales (exclusive of depreciation and amortization shown separately below):
Cost of sales	$ 8,592	$ 6,127	$ 16,202	$ 12,749

Net Income (Loss) Per Share (Tables)

6 Months Ended

Jun. 30, 2023

Earnings Per Share [Abstract]

Schedule of information required to compute basic and diluted net loss per share


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Net loss attributable to Clean Energy Fuels Corp.	$	(13,235)	$	(16,301)	$	(37,426)	$	(54,998)

Weighted-average common shares outstanding		222,433,900		222,908,402		222,496,426		222,813,286
Dilutive effect of potential common shares from restricted stock units, stock options and stock warrants		—		—		—		—
Weighted-average common shares outstanding - diluted		222,433,900		222,908,402		222,496,426		222,813,286
Basic and diluted loss per share	$	(0.06)	$	(0.07)	$	(0.17)	$	(0.25)

Schedule of potentially dilutive securities that have been excluded from the diluted net loss per share calculations because their effect would have been antidilutive


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Stock options		16,410,764		18,154,864		16,410,764		18,154,864
Restricted stock units		680,191		367,145		680,191		367,145
Amazon warrant shares		58,767,714		58,767,714		58,767,714		58,767,714
Total		75,858,669		77,289,723		75,858,669		77,289,723

Stock-Based Compensation - Amazon Warrant Activity (Details) - Amazon Warrant	6 Months Ended
	Jun. 30, 2023 USD ($) shares
Class of Warrant or Right [Line Items]
Outstanding and unvested Beginning Balance \| $	$ 42,314,667
Granted	0
Vested	(1,763,112)
Outstanding and unvested as of Ending Balance \| $	$ 40,551,555
Number of warrants vested	1,763,112

Stockholders' Equity

6 Months Ended

Jun. 30, 2023

Stockholders' Equity Note [Abstract]

Stockholders' Equity

Note 15—Stockholders’ Equity

Authorized Shares

On June 14, 2021, the Company’s stockholders approved an increase in the number of shares of common stock the Company is authorized to issue from 304,000,000 to 454,000,000. As of June 30, 2023, the Company is authorized to issue 455,000,000 shares, of which 454,000,000 shares of capital stock are designated common stock and 1,000,000 shares are designated preferred stock.

Share Repurchase Program

On March 12, 2020, the Company’s Board of Directors approved a share repurchase program of up to $30.0 million (exclusive of fees and commissions) of the Company’s outstanding common stock (the “Repurchase Program”). On December 7, 2021, the Company’s Board of Directors approved an increase in the aggregate purchase amount under the Repurchase Program from $30.0 million to $50.0 million (exclusive of fees and commissions). The Repurchase Program does not have an expiration date, and it may be suspended or discontinued at any time. As of June 30, 2023, the Company has utilized a total of $23.5 million under the Repurchase Program from its inception to repurchase 9,387,340 shares of common stock, and a total of $26.5 million of authorized funds remain available for common stock repurchase under the Repurchase Program. The Repurchase Program does not obligate the Company to acquire any specific number of shares. Repurchases under the Repurchase Program may be effected from time to time through open market purchases, privately negotiated transactions, structured or derivative transactions, including accelerated share repurchase transactions, or other methods of acquiring shares, in each case subject to market conditions, applicable securities laws and other relevant factors. Repurchases may also be made under plans complying with Rule 10b5-1 under the Securities Exchange Act of 1934, as amended.

Revenue from Contracts with Customers - Remaining Performance Obligations (Details) $ in Millions	Jun. 30, 2023 USD ($)
Remaining Performance Obligations
Revenue, remaining performance obligation, amount	$ 28.5
Minimum
Remaining Performance Obligations
Revenue, remaining performance obligation, expected timing of satisfaction, period	12 months
Maximum
Remaining Performance Obligations
Revenue, remaining performance obligation, expected timing of satisfaction, period	24 months

Land, Property and Equipment (Tables)

6 Months Ended

Jun. 30, 2023

Property, Plant and Equipment [Abstract]

Summary of land, property and equipment

Land, property and equipment, net as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Land	$	3,476	$	3,620
LNG liquefaction plants		94,790		96,607
Station equipment		353,104		379,272
Trailers		73,253		72,553
Other equipment		106,184		99,795
Construction in progress		91,105		117,921
		721,912		769,768
Less accumulated depreciation		(457,844)		(477,305)
Total land, property and equipment, net	$	264,068	$	292,463

Accrued Liabilities (Tables)

6 Months Ended

Jun. 30, 2023

Payables and Accruals [Abstract]

Schedule of accrued liabilities

Accrued liabilities as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Accrued alternative fuels incentives ⁽¹⁾	$	34,239	$	31,993
Accrued employee benefits		5,128		4,863
Accrued gas and equipment purchases		22,008		13,480
Accrued interest		1,827		1,616
Accrued property and other taxes		3,782		3,525
Accrued salaries and wages		6,857		5,326
Embedded derivatives		—		80
Other ⁽²⁾		16,238		15,726
Total accrued liabilities	$	90,079	$	76,609

(1)	Includes amount for RINs, LCFS Credits, and AFTC payable to third parties.

(2)	No individual item in “Other” exceeds 5% of total current liabilities.

General (Policies)	6 Months Ended
General (Policies)	Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Basis of Presentation The accompanying interim unaudited condensed consolidated financial statements include the accounts of the Company and its subsidiaries, and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s consolidated financial position as of June 30, 2023, results of operations, comprehensive loss, and stockholders’ equity for the three and six months ended June 30, 2022 and 2023, and cash flows for the six months ended June 30, 2022 and 2023. All intercompany accounts and transactions have been eliminated in consolidation. The results of operations for the three and six months ended June 30, 2022 and 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023 or for any other interim period or any future year. Certain information and disclosures normally included in the notes to consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”), but the resultant disclosures contained herein are in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) as they apply to interim reporting. The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2022 that are included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2023.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying condensed consolidated financial statements and these notes. Actual results could differ from those estimates and may result in material effects on the Company’s operating results and financial position. Significant estimates made in preparing the accompanying condensed consolidated financial statements include (but are not limited to) those related to revenue recognition, fair value measurements, goodwill and long-lived asset valuations and impairment assessments, income tax valuations, stock-based compensation expense and stock-based sales incentive charges.
Amazon Warrant	Amazon Warrant The Amazon Warrant (defined in Note 14) is accounted for as an equity instrument and measured in accordance with Accounting Standards Codification (“ASC”) 718, Compensation – Stock Compensation. This instrument is classified in the condensed consolidated statements of operations in accordance with ASC 606, Revenue from Contracts with Customers, which states that for awards granted to a customer that are not in exchange for distinct goods or services, the fair value of the awards earned based on service or performance conditions is recorded as a reduction of the transaction price. To determine the fair value of the Amazon Warrant in accordance with ASC 718, the Company used the Black-Scholes option pricing model, which is based in part on assumptions that require management to use judgment. Based on the fair value of the award, the Company determines the amount of non-cash stock-based sales incentive charges on the customer’s pro-rata achievement of vesting conditions, which is recorded as a reduction of revenue in the condensed consolidated statements of operations. See Note 14 for additional information.
Tourmaline Joint Development	Tourmaline Joint Development In April 2023, the Company and Tourmaline Oil Corp. (“Tourmaline”) announced a CAD $70 million Joint Development Agreement to build and operate a network of CNG stations along key highway corridors across Western Canada. Under a 50-50 shared investment, the Company and Tourmaline expect to construct and commission up to 20 CNG fueling stations over the next five years, allowing heavy-duty trucks and other commercial transportation fleets that operate in the area to transition to the use of CNG, a lower carbon alternative to gasoline and diesel. Costs associated with station construction and profit and loss arising from station operation are shared 50-50 between the Company and Tourmaline. This arrangement between the Company and Tourmaline to jointly develop, build and operate CNG fueling stations is accounted for in accordance with ASC 808, Collaborative Arrangements, which states that (1) costs incurred and revenue generated from transactions with third parties be separately recorded by each participant in its own financial statements, (2) the participant who is deemed to be the principal for a given transaction under ASC 606, Revenue from Contracts with Customers, will record the transaction on a gross basis in its financial statements, and (3) payments between participants that are within the scope of other authoritative accounting literature on income statement classification shall be accounted for using the relevant provisions of that literature. If the payments are not within the scope of other authoritative accounting literature, then the income statement classification for the payments shall be based on an analogy to authoritative accounting literature or if there is no appropriate analogy, a reasonable, rational, and consistently applied accounting policy election. The Company determined that it is the principal for the revenue generated from third parties under this collaborative arrangement with Tourmaline in accordance with ASC 606; as such, the associated revenue and cost of sales generated and incurred are recognized on a gross basis in the condensed consolidated statements of operations. Net participation of profit and loss owed to or from Tourmaline is recorded as an increase or decrease to cost of sales, respectively, as the transaction is not deemed to be with a customer within the scope of ASC 606. Capitalized station costs are presented at half of the total development and construction costs in the condensed consolidated balance sheets, corresponding to the Company’s 50% ownership in the shared assets.
Recently Adopted Accounting Pronouncements	Recently Issued Accounting Pronouncements In March 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-01, Leases (Topic 842): Common Control Arrangements. This ASU permits private entities with common control arrangements that may contain or be leases to use any written terms and conditions between the parties, without regard to their legal enforceability, to identify, classify and account for common control leases. In addition, all lessees (public or private), in general, amortize leasehold improvements related to a common control lease over their useful life to the common control group, regardless of the ASC 842 lease term, as long as they continue to control the use of the underlying leased asset. The ASU is effective for fiscal years, including interim periods within those years, beginning after December 15, 2023, with early adoption allowed. The Company is currently evaluating the impact of adopting this new ASU and does not expect the adoption to have a material effect on the Company’s condensed consolidated financial statements.
Revenue Recognition	Revenue Recognition Overview The Company recognizes revenue when control of the promised goods or services is transferred to its customers, in an amount that reflects the consideration to which it expects to be entitled in exchange for the goods or services. To achieve that core principle, a five-step approach is applied: (1) identify the contract with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract, and (5) recognize revenue allocated to each performance obligation when the Company satisfies the performance obligation. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer, and is the unit of account for revenue recognition.
Basis of Presentation	Basis of Presentation The accompanying interim unaudited condensed consolidated financial statements include the accounts of the Company and its subsidiaries, and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary to state fairly the Company’s consolidated financial position as of June 30, 2023, results of operations, comprehensive loss, and stockholders’ equity for the three and six months ended June 30, 2022 and 2023, and cash flows for the six months ended June 30, 2022 and 2023. All intercompany accounts and transactions have been eliminated in consolidation. The results of operations for the three and six months ended June 30, 2022 and 2023 are not necessarily indicative of the results to be expected for the year ending December 31, 2023 or for any other interim period or any future year. Certain information and disclosures normally included in the notes to consolidated financial statements have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”), but the resultant disclosures contained herein are in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) as they apply to interim reporting. The accompanying condensed consolidated financial statements should be read in conjunction with the consolidated financial statements as of and for the year ended December 31, 2022 that are included in the Company’s Annual Report on Form 10-K filed with the SEC on February 28, 2023.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the accompanying condensed consolidated financial statements and these notes. Actual results could differ from those estimates and may result in material effects on the Company’s operating results and financial position. Significant estimates made in preparing the accompanying condensed consolidated financial statements include (but are not limited to) those related to revenue recognition, fair value measurements, goodwill and long-lived asset valuations and impairment assessments, income tax valuations, stock-based compensation expense and stock-based sales incentive charges.
Revenue Recognition	Revenue Recognition Overview The Company recognizes revenue when control of the promised goods or services is transferred to its customers, in an amount that reflects the consideration to which it expects to be entitled in exchange for the goods or services. To achieve that core principle, a five-step approach is applied: (1) identify the contract with a customer, (2) identify the performance obligations in the contract, (3) determine the transaction price, (4) allocate the transaction price to the performance obligations in the contract, and (5) recognize revenue allocated to each performance obligation when the Company satisfies the performance obligation. A performance obligation is a promise in a contract to transfer a distinct good or service to the customer, and is the unit of account for revenue recognition.
Amazon Warrant	Amazon Warrant The Amazon Warrant (defined in Note 14) is accounted for as an equity instrument and measured in accordance with Accounting Standards Codification (“ASC”) 718, Compensation – Stock Compensation. This instrument is classified in the condensed consolidated statements of operations in accordance with ASC 606, Revenue from Contracts with Customers, which states that for awards granted to a customer that are not in exchange for distinct goods or services, the fair value of the awards earned based on service or performance conditions is recorded as a reduction of the transaction price. To determine the fair value of the Amazon Warrant in accordance with ASC 718, the Company used the Black-Scholes option pricing model, which is based in part on assumptions that require management to use judgment. Based on the fair value of the award, the Company determines the amount of non-cash stock-based sales incentive charges on the customer’s pro-rata achievement of vesting conditions, which is recorded as a reduction of revenue in the condensed consolidated statements of operations. See Note 14 for additional information.
Recently Adopted Accounting Pronouncements	Recently Issued Accounting Pronouncements In March 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2023-01, Leases (Topic 842): Common Control Arrangements. This ASU permits private entities with common control arrangements that may contain or be leases to use any written terms and conditions between the parties, without regard to their legal enforceability, to identify, classify and account for common control leases. In addition, all lessees (public or private), in general, amortize leasehold improvements related to a common control lease over their useful life to the common control group, regardless of the ASC 842 lease term, as long as they continue to control the use of the underlying leased asset. The ASU is effective for fiscal years, including interim periods within those years, beginning after December 15, 2023, with early adoption allowed. The Company is currently evaluating the impact of adopting this new ASU and does not expect the adoption to have a material effect on the Company’s condensed consolidated financial statements.

- Definition

Disclosure of accounting policy for revenue from contract with customer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 19
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-19

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-18

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-18

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 20
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-20

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (e)
-SubTopic 10
-Topic 235
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483426/235-10-50-4

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

+ Details

Fair Value Measurements - Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Assets:
Available-for-sale securities	$ 138,569	$ 139,569
Short-term investments	138,569	139,569
U.S. government securities
Assets:
Available-for-sale securities	138,039	64,880
Zero coupon bonds
Assets:
Available-for-sale securities		74,159
Certificates of deposit
Assets:
Available-for-sale securities	530	530
Fair value measured on recurring basis \| U.S. government securities
Assets:
Available-for-sale securities	138,039	64,880
Fair value measured on recurring basis \| Zero coupon bonds
Assets:
Available-for-sale securities		74,159
Fair value measured on recurring basis \| Convertible promissory note
Assets:
Available-for-sale securities		1,880
Short-term investments	4,295
Fair value measured on recurring basis \| Certificates of deposit
Assets:
Short-term investments		530
Derivative assets	530
Fair value measured on recurring basis \| Embedded derivatives
Assets:
Derivative assets	6,837	6,755
Liabilities:
Derivative liabilities	80
Fair value measured on recurring basis \| Commodity swap contracts
Liabilities:
Derivative liabilities	2,779	3,845
Fair value measured on recurring basis \| Level 1 \| U.S. government securities
Assets:
Available-for-sale securities	138,039	64,880
Fair value measured on recurring basis \| Level 1 \| Zero coupon bonds
Assets:
Available-for-sale securities		0
Fair value measured on recurring basis \| Level 1 \| Convertible promissory note
Assets:
Available-for-sale securities		0
Short-term investments	0
Fair value measured on recurring basis \| Level 1 \| Certificates of deposit
Assets:
Short-term investments		0
Derivative assets	0
Fair value measured on recurring basis \| Level 1 \| Embedded derivatives
Assets:
Derivative assets		0
Liabilities:
Derivative liabilities	0
Fair value measured on recurring basis \| Level 1 \| Commodity swap contracts
Liabilities:
Derivative liabilities	0	0
Fair value measured on recurring basis \| Level 2 \| U.S. government securities
Assets:
Available-for-sale securities	0	0
Fair value measured on recurring basis \| Level 2 \| Zero coupon bonds
Assets:
Available-for-sale securities		74,159
Fair value measured on recurring basis \| Level 2 \| Convertible promissory note
Assets:
Available-for-sale securities		0
Short-term investments	0
Fair value measured on recurring basis \| Level 2 \| Certificates of deposit
Assets:
Short-term investments		530
Derivative assets	530
Fair value measured on recurring basis \| Level 2 \| Embedded derivatives
Assets:
Derivative assets		0
Liabilities:
Derivative liabilities	0
Fair value measured on recurring basis \| Level 2 \| Commodity swap contracts
Liabilities:
Derivative liabilities	0	0
Fair value measured on recurring basis \| Level 3 \| U.S. government securities
Assets:
Available-for-sale securities	0	0
Fair value measured on recurring basis \| Level 3 \| Zero coupon bonds
Assets:
Available-for-sale securities		0
Fair value measured on recurring basis \| Level 3 \| Convertible promissory note
Assets:
Available-for-sale securities		1,880
Short-term investments	4,295
Fair value measured on recurring basis \| Level 3 \| Certificates of deposit
Assets:
Short-term investments		0
Derivative assets	0
Fair value measured on recurring basis \| Level 3 \| Embedded derivatives
Assets:
Derivative assets	6,837	6,755
Liabilities:
Derivative liabilities	80
Fair value measured on recurring basis \| Level 3 \| Commodity swap contracts
Liabilities:
Derivative liabilities	$ 2,779	$ 3,845

Leases

6 Months Ended

Jun. 30, 2023

Leases

Leases

Note 18—Leases

Lessor Accounting

The Company leases fueling station equipment to customers pursuant to agreements that contain an option to extend and an end-of-term purchase option. Receivables from these leases are accounted for as finance leases, specifically sales-type leases, and are included in “Other receivables” and “Notes receivable and other long-term assets, net” in the accompanying condensed consolidated balance sheets.

The Company recognizes the net investment in the lease as the sum of the lease receivable and the unguaranteed residual value, both of which are measured at the present value using the interest rate implicit in the lease.

During each of the three months ended June 30, 2022 and 2023, the Company recognized $0.1 million in “Interest income” on its lease receivables. During each of the six months ended June 30, 2022 and 2023, the Company recognized $0.2 million in “Interest income” on its lease receivables.

The following schedule represents the Company’s maturities of lease receivables as of June 30, 2023 (in thousands):


Fiscal year:
Remainder of 2023	$	481
2024		962
2025		962
2026		985
2027		1,105
Thereafter		1,218
Total minimum lease payments		5,713
Less amount representing interest		(1,260)
Present value of lease receivables	$	4,453

Derivative Instruments and Hedging Activities (Tables)

6 Months Ended

Jun. 30, 2023

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Summary of commodity derivative activity

Commodity swaps and embedded derivatives as of December 31, 2022 consisted of the following (in thousands):


	Gross Amounts		Gross Amounts		Net Amount
	Recognized		Offset		Presented
Assets:
Fueling agreements:
Prepaid expenses and other current assets	$	1,640	$	—	$	1,640
Notes receivable and other long-term assets, net		5,115		—		5,115
Total derivative assets	$	6,755	$	—	$	6,755
Liabilities:
Commodity swaps:
Current portion of derivative liabilities, related party	$	2,415	$	—	$	2,415
Long-term portion of derivative liabilities, related party		1,430		—		1,430
Total derivative liabilities	$	3,845	$	—	$	3,845

Commodity swaps and embedded derivatives as of June 30, 2023 consisted of the following (in thousands):


	Gross Amounts		Gross Amounts		Net Amount
	Recognized		Offset		Presented
Assets:
Fueling agreements:
Prepaid expenses and other current assets	$	2,299	$	—	$	2,299
Notes receivable and other long-term assets, net		4,538		—		4,538
Total derivative assets	$	6,837	$	—	$	6,837
Liabilities:
Commodity swaps:
Current portion of derivative liabilities, related party	$	2,779	$	—	$	2,779
Fueling agreements:
Accrued liabilities		80		—		80
Total derivative liabilities	$	2,859	$	—	$	2,859

Schedule of weighted-average price of open commodity swap contract

The following table reflects the weighted-average price of open commodity swap contracts as of December 31, 2022 and June 30, 2023, by year with associated volumes:


	December 31, 2022			June 30, 2023
	Volumes	Weighted-Average Price per		Volumes	Weighted-Average Price per
Year	(Diesel Gallons)	Diesel Gallon		(Diesel Gallons)	Diesel Gallon
2023	5,000,000	$	3.18	2,500,000	$	3.18
2024	1,875,000	$	3.18	1,875,000	$	3.18

Net Loss Per Share - Anti-dilutive Securities (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net Loss Per Share
Anti-dilutive securities (in shares)	77,289,723	75,858,669	77,289,723	75,858,669
Stock options
Net Loss Per Share
Anti-dilutive securities (in shares)	18,154,864	16,410,764	18,154,864	16,410,764
Restricted stock units
Net Loss Per Share
Anti-dilutive securities (in shares)	367,145	680,191	367,145	680,191
Amazon warrant shares
Net Loss Per Share
Anti-dilutive securities (in shares)	58,767,714	58,767,714	58,767,714	58,767,714

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Current assets:
Cash, cash equivalents and current portion of restricted cash	$ 55,162	$ 125,950
Short-term investments	138,569	139,569
Accounts receivable, net of allowance of $1,375 and $1,501 as of December 31, 2022 and June 30, 2023, respectively	74,746	91,430
Other receivables	27,088	17,026
Inventory	38,517	37,144
Prepaid expenses and other current assets	58,279	60,601
Total current assets	392,361	471,720
Operating lease right-of-use assets	63,093	52,586
Land, property and equipment, net	292,463	264,068
Notes receivable and other long-term assets, net	31,004	30,467
Investments in other entities	196,770	193,273
Goodwill	64,328	64,328
Intangible assets, net	6,365	5,915
Total assets	1,046,384	1,082,357
Current liabilities:
Current portion of debt	38	93
Current portion of finance lease obligations	961	948
Current portion of operating lease obligations	5,075	4,206
Accounts payable	37,943	44,435
Accrued liabilities	76,609	90,079
Deferred revenue	4,920	5,970
Derivative liabilities, related party	2,779	2,415
Total current liabilities	128,325	148,146
Long-term portion of debt	144,837	145,471
Long-term portion of finance lease obligations	2,024	2,134
Long-term portion of operating lease obligations	59,393	48,911
Long-term portion of derivative liabilities, related party	0	1,430
Other long-term liabilities	8,908	8,794
Total liabilities	343,487	354,886
Commitments and contingencies (Note 17)
Stockholders' equity:
Preferred stock, $0.0001 par value. 1,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.0001 par value. 454,000,000 shares authorized; 222,437,429 shares and 222,910,057 shares issued and outstanding as of December 31, 2022 and June 30, 2023, respectively	22	22
Additional paid-in capital	1,582,009	1,553,668
Accumulated deficit	(884,973)	(829,975)
Accumulated other comprehensive loss	(1,319)	(3,722)
Total Clean Energy Fuels Corp. stockholders' equity	695,739	719,993
Noncontrolling interest in subsidiary	7,158	7,478
Total stockholders' equity	702,897	727,471
Total liabilities and stockholders' equity	$ 1,046,384	$ 1,082,357

Cash, Cash Equivalents and Restricted Cash

6 Months Ended

Jun. 30, 2023

Cash and Cash Equivalents [Abstract]

Cash, Cash Equivalents and Restricted Cash

Note 4—Cash, Cash Equivalents and Restricted Cash

Cash, cash equivalents and restricted cash as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Current assets:
Cash and cash equivalents	$	123,950	$	53,150
Restricted cash - standby letter of credit		2,000		2,012
Total cash, cash equivalents and current portion of restricted cash	$	125,950	$	55,162

Total cash, cash equivalents and restricted cash	$	125,950	$	55,162

The Company considers all highly liquid investments with maturities of three months or less on the date of acquisition to be cash equivalents.

The Company places its cash and cash equivalents with high credit quality financial institutions. At times, such balances may be in excess of the Federal Deposit Insurance Corporation (“FDIC”) and Canadian Deposit Insurance Corporation (“CDIC”) limits. Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash deposits. The amounts in excess of FDIC and CDIC limits were approximately $124.8 million and $54.0 million as of December 31, 2022 and June 30, 2023, respectively.

The Company classifies restricted cash as short-term and a current asset if the cash is expected to be used in operations within a year or to acquire a current asset. Otherwise, the restricted cash is classified as long-term. The Company deposited $2.0 million, in the form of a certificate of deposit, at PlainsCapital Bank as collateral for the standby letter of credit issued to Chevron Products Company, a division of Chevron U.S.A. Inc., in connection with the Company’s Adopt-A-Port program. The $2.0 million certificate of deposit is classified as short-term restricted cash and a current asset and is included in “Cash, cash equivalents and current portion of restricted cash” in the accompanying condensed consolidated balance sheets as of December 31, 2022 and June 30, 2023.

Investments in Other Entities and Noncontrolling Interest in a Subsidiary - TotalEnergies Joint Venture (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Nov. 30, 2021	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 28, 2023	Dec. 31, 2022	Oct. 12, 2021	Mar. 03, 2021
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments			$ (1,915)	$ (1,193)	$ (3,805)	$ (2,870)
Advance to DR JV					5,500	0
TotalEnergies
Schedule of Equity Method Investments [Line Items]
Income (loss) from equity method investments			(1,000)	$ (100)	(1,400)	$ (100)
Investment balance	$ 8,600		$ 8,600		$ 8,600			$ 4,500
TotalEnergies \| ADG RNG Production Facilities
Schedule of Equity Method Investments [Line Items]
Investment commitment of equity in production projects										$ 400,000
Investment commitment in joint venture										50,000
TotalEnergies \| ADG RNG Production Facilities \| TotalEnergies S.E.
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture										$ 50,000
TotalEnergies \| DR Development Agreement
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture							$ 5,500		$ 7,000
Initial contribution commitment		$ 4,800
Capital call contribution amount							$ 11,000
Contribution to joint venture	5,500
Advance to DR JV	5,500
Advance amount expected to refund	$ 5,500
TotalEnergies \| DR Development Agreement \| TotalEnergies S.E.
Schedule of Equity Method Investments [Line Items]
Investment commitment in joint venture									$ 7,000
Initial contribution commitment		$ 4,800

Derivative Instruments and Hedging Activities - Narrative (Details) - Not Designated as Hedging Instrument - Commodity swaps gal in Millions	1 Months Ended	6 Months Ended	12 Months Ended
	Oct. 31, 2018 contract gal	Jun. 30, 2023 $ / gal gal	Dec. 31, 2022 $ / gal gal
Derivative [Line Items]
Derivative asset, number of instruments held \| contract	2
Volumes (Diesel Gallons) \| gal	5.0	4.4	6.9
Weighted-average price per diesel gallon (in usd per gallon) \| $ / gal		3.18	3.18

Other Receivables (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Other Receivables
Other receivables	$ 27,088	$ 17,026
Loans to customers to finance vehicle purchases
Other Receivables
Other receivables	422	523
Accrued customer billings
Other Receivables
Other receivables	7,489	4,910
Fuel tax credits
Other Receivables
Other receivables	7,376	9,462
Other
Other Receivables
Other receivables	$ 11,801	$ 2,131

Accrued Liabilities

6 Months Ended

Jun. 30, 2023

Payables and Accruals [Abstract]

Accrued Liabilities

Note 11—Accrued Liabilities

Accrued liabilities as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Accrued alternative fuels incentives ⁽¹⁾	$	34,239	$	31,993
Accrued employee benefits		5,128		4,863
Accrued gas and equipment purchases		22,008		13,480
Accrued interest		1,827		1,616
Accrued property and other taxes		3,782		3,525
Accrued salaries and wages		6,857		5,326
Embedded derivatives		—		80
Other ⁽²⁾		16,238		15,726
Total accrued liabilities	$	90,079	$	76,609

(1)	Includes amount for RINs, LCFS Credits, and AFTC payable to third parties.

(2)	No individual item in “Other” exceeds 5% of total current liabilities.

Fair Value Measurements - Transfers (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2023	Dec. 31, 2022
Fair Value Disclosures [Abstract]
Asset transferred level 3 net	$ 0.0	$ 0.0
Liabilities transferred level 3 net	$ 0.0	$ 0.0

General (Details) - Tourmaline Joint Development - Tourmaline Oil Corp. $ in Millions	1 Months Ended
	Apr. 30, 2023 CAD ($) item
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Agreement amount \| $	$ 70
Ownership interest (as a percent)	50.00%
Maximum number of CNG fueling stations expect to construct and commission \| item	20
Period for construction and commission of CNG fueling stations	5 years

Stock-Based Compensation - Amazon Warrant (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Jun. 14, 2021	Apr. 16, 2021
Subsidiary, Sale of Stock [Line Items]
Contra revenue charge			$ 27,652	$ 8,533
Amazon Warrant \| Transaction Agreement With Amazon
Subsidiary, Sale of Stock [Line Items]
Aggregate number of warrant shares (in shares)						5,625,959	53,141,755
Total discretionary fuel purchases							$ 500,000
Exercise price of the warrant (in dollars per share)						$ 13.49	$ 13.49
Amazon Warrant \| Prepaid expenses and other current assets
Subsidiary, Sale of Stock [Line Items]
Customer incentive assets	$ 10,600		10,600		$ 22,200
Amazon Warrant \| Vesting over the second year \| Transaction Agreement With Amazon
Subsidiary, Sale of Stock [Line Items]
Contra revenue charge	$ 13,900	$ 4,800	$ 27,700	$ 8,500

Alternative Fuels Excise Tax Credit

6 Months Ended

Jun. 30, 2023

Alternative Fuel Excise Tax Credit

Alternative Fuels Excise Tax Credit

Note 19—Alternative Fuel Excise Tax Credit

Under separate pieces of U.S. federal legislation, the Company was eligible to receive AFTC for its natural gas vehicle fuel sales made between October 1, 2006 and December 31, 2021. In August 2022, the Inflation Reduction Act of 2022 was enacted, extending AFTC for an additional three years through December 31, 2024, beginning retroactively to January 1, 2022. The AFTC incentive in the extension period under the Inflation Reduction Act of 2022 is equal to $0.50 per gasoline gallon equivalent of CNG and $0.50 per diesel gallon of LNG that the Company sells as vehicle fuel.

Based on the service relationship with its customers, either the Company or its customers claim the credit. The Company records its AFTC, if any, as revenue in its condensed consolidated statements of operations because the credits are fully payable to the Company and do not offset income tax liabilities. As such, the credits are not deemed income tax credits under the accounting guidance applicable to income taxes.

Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2023

Stockholders' Equity Note [Abstract]

Summary of compensation expense and related income tax benefit related to the stock-based compensation expense recognized


	Three Months Ended				Six Months Ended
	June 30,				June 30,
	2022		2023		2022		2023
Stock-based compensation expense, net of $0 tax in 2022 and 2023	$	6,468	$	6,093	$	14,721	$	12,189

Schedule of fair value measurement of warrants

The Company estimated the fair value of its outstanding commodity swap contracts based on the following inputs as of December 31, 2022 and June 30, 2023:


	December 31, 2022			June 30, 2023
Significant Unobservable Inputs	Input Range	Weighted Average		Input Range	Weighted Average
ULSD Gulf Coast Forward Curve	$2.35 - $2.59	$	2.48	$1.98 - $2.23	$	2.13
Historical Differential to PADD 3 Diesel	$0.88 - $1.62	$	1.13	$0.92 - $1.62	$	1.14
Historical Differential to PADD 5 Diesel	$1.89 - $3.00	$	2.30	$1.89 - $3.02	$	2.36


	December 31, 2022			June 30, 2023
Significant Unobservable Inputs	Input Range	Weighted Average		Input Range	Weighted Average
ULSD Gulf Coast Forward Curve	$2.35 - $2.59	$	2.48	$1.98 - $2.23	$	2.13
Historical Differential to PADD 3 Diesel	$0.88 - $1.62	$	1.13	$0.92 - $1.62	$	1.14
Historical Differential to PADD 5 Diesel	$1.91 - $3.05	$	2.31	$1.89 - $3.02	$	2.36

Schedule of warrant activity

The following table summarizes the Amazon Warrant activity for the six months ended June 30, 2023:


		Warrant
		Shares
Outstanding and unvested as of December 31, 2022		42,314,667
Granted		—
Vested		(1,763,112)
Outstanding and unvested as of June 30, 2023		40,551,555

Derivative Instruments and Hedging Activities

6 Months Ended

Jun. 30, 2023

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Derivative Instruments and Hedging Activities

Note 6—Derivative Instruments and Hedging Activities

In October 2018, the Company executed two commodity swap contracts with TotalEnergies Gas & Power North America, an affiliate of TotalEnergies and THUSA (as defined in Note 12), for a total of 5.0 million diesel gallons annually from April 1, 2019 to June 30, 2024. These commodity swap contracts are used to manage diesel price fluctuation risks related to the natural gas fuel supply commitments the Company makes in its fueling agreements with fleet operators that participate in the Zero Now truck financing program. These contracts are not designated as accounting hedges and as a result, changes in the fair value of these derivative instruments are recognized in “Product revenue” in the accompanying condensed consolidated statements of operations.

The Company has entered into fueling agreements with fleet operators under the Zero Now truck financing program. Certain of these fueling agreements contain a pricing feature indexed to diesel, which the Company determined to be an embedded derivative and is recorded at fair value at the time of execution, with the changes in fair value of the embedded derivative recognized in “Product revenue” in the accompanying condensed consolidated statements of operations.

Commodity swaps and embedded derivatives as of December 31, 2022 consisted of the following (in thousands):


	Gross Amounts		Gross Amounts		Net Amount
	Recognized		Offset		Presented
Assets:
Fueling agreements:
Prepaid expenses and other current assets	$	1,640	$	—	$	1,640
Notes receivable and other long-term assets, net		5,115		—		5,115
Total derivative assets	$	6,755	$	—	$	6,755
Liabilities:
Commodity swaps:
Current portion of derivative liabilities, related party	$	2,415	$	—	$	2,415
Long-term portion of derivative liabilities, related party		1,430		—		1,430
Total derivative liabilities	$	3,845	$	—	$	3,845

Commodity swaps and embedded derivatives as of June 30, 2023 consisted of the following (in thousands):


	Gross Amounts		Gross Amounts		Net Amount
	Recognized		Offset		Presented
Assets:
Fueling agreements:
Prepaid expenses and other current assets	$	2,299	$	—	$	2,299
Notes receivable and other long-term assets, net		4,538		—		4,538
Total derivative assets	$	6,837	$	—	$	6,837
Liabilities:
Commodity swaps:
Current portion of derivative liabilities, related party	$	2,779	$	—	$	2,779
Fueling agreements:
Accrued liabilities		80		—		80
Total derivative liabilities	$	2,859	$	—	$	2,859

As of December 31, 2022 and June 30, 2023, the Company had a total volume on open commodity swap contracts of 6.9 million and 4.4 million diesel gallons, respectively, at a weighted-average price of approximately $3.18 per gallon.

The following table reflects the weighted-average price of open commodity swap contracts as of December 31, 2022 and June 30, 2023, by year with associated volumes:


	December 31, 2022			June 30, 2023
	Volumes	Weighted-Average Price per		Volumes	Weighted-Average Price per
Year	(Diesel Gallons)	Diesel Gallon		(Diesel Gallons)	Diesel Gallon
2023	5,000,000	$	3.18	2,500,000	$	3.18
2024	1,875,000	$	3.18	1,875,000	$	3.18

Leases (Tables)

6 Months Ended

Jun. 30, 2023

Leases

Schedule of maturities of lease receivables

The following schedule represents the Company’s maturities of lease receivables as of June 30, 2023 (in thousands):


Fiscal year:
Remainder of 2023	$	481
2024		962
2025		962
2026		985
2027		1,105
Thereafter		1,218
Total minimum lease payments		5,713
Less amount representing interest		(1,260)
Present value of lease receivables	$	4,453

Other Receivables (Tables)

6 Months Ended

Jun. 30, 2023

Receivables [Abstract]

Schedule of other receivables

Other receivables as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Loans to customers to finance vehicle purchases	$	523	$	422
Accrued customer billings		4,910		7,489
Fuel tax credits		9,462		7,376
Other		2,131		11,801
Total other receivables	$	17,026	$	27,088

Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Statement of Cash Flows [Abstract]
Capitalized interest paid, respectively	$ 581	$ 0

Debt

6 Months Ended

Jun. 30, 2023

Debt Disclosure [Abstract]

Debt

Note 12—Debt

Debt obligations as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31, 2022
			Unamortized Debt		Balance, Net of
	Principal Balance		Financing Costs		Financing Costs
Riverstone term loan	$	150,000	$	4,529	$	145,471
Other debt		93		—		93
Total debt		150,093		4,529		145,564
Less amounts due within one year		(93)		—		(93)
Total long-term debt	$	150,000	$	4,529	$	145,471


	June 30, 2023
			Unamortized Debt		Balance, Net of
	Principal Balance		Financing Costs		Financing Costs
Riverstone term loan	$	150,000	$	5,380	$	144,620
Other debt		255		—		255
Total debt		150,255		5,380		144,875
Less amounts due within one year		(38)		—		(38)
Total long-term debt	$	150,217	$	5,380	$	144,837

Riverstone Credit Agreement

On December 22, 2022 (the “Closing Date”), the Company entered into a Senior Secured First Lien Term Loan Credit Agreement (the “Riverstone Credit Agreement”) with a syndicate of lenders. Pursuant to the Riverstone Credit Agreement, the lenders made a $150,000,000 sustainability-linked senior secured term loan (the “Sustainability-Linked Term Loan”) to the Company, a transaction aligned with the five pillars of the Loan Syndications and Trading Association’s sustainability-linked loan principles. Payments for the Sustainability-Linked Term Loan are interest only with a balloon principal payment due on the maturity date, which is December 22, 2026. The Sustainability-Linked Term Loan bears interest, at the option of the Company, at (a) Adjusted Term SOFR or (b) the Alternate Base Rate (“ABR”), which is defined as the greater of (i) the Prime Rate, (ii) the Federal Funds Effective Rate plus 0.50%, and (iii) one-month Adjusted Term SOFR plus 1.00%, plus an applicable margin of 6.50% for interest rate based on SOFR or 5.50% for election under the ABR through the second anniversary of the Closing Date. After the second anniversary of the Closing Date, the applicable margin increases to 7.25% for election under SOFR or 6.25% for election under the ABR. The applicable margin is subject to a sustainability rate adjustment feature, which may increase the applicable margin by 25 basis points if certain KPI metric is not met for fiscal years beginning after December 31, 2024. The sustainability rate adjustment feature shall be applied retroactively to commence as of December 31, 2025. Interest rate for the Sustainability-Linked Term Loan has an interest rate floor of 1.50% for election under SOFR and 2.50% for election under the ABR. Proceeds from the Sustainability-Linked Term Loan were or will be used to repay certain existing indebtedness of the Company, to finance permitted investments from time to time, to pay transaction costs related to the Riverstone Credit Agreement and for other general corporate purposes. In connection with the Sustainability-Linked Term Loan, the Company is obligated to pay other facility fees customary for credit facilities of similar size and type.

The Company has the option to prepay all or any portion of the amounts owed prior to the maturity date and is subject to customary mandatory prepayments clauses. All prepayments and all other payments of the Sustainability-Linked Term Loan principal are subject to a call premium (2.0% from the one-year anniversary of the Closing Date to the date that is eighteen months after the Closing Date, 2.5% after the date that is eighteen months after the Closing Date to the date that is twenty-four months after the Closing Date, and 3% at any time thereafter). No call premium applies to any prepayment of the Sustainability-Linked Term Loan made prior to the first anniversary of the Closing Date. In conjunction with the Riverstone Credit Agreement, the Company and certain of its subsidiaries entered into a Guarantee and Collateral Agreement (the “Security Agreement”) in favor of the lenders. Under the Security Agreement, the Company and certain of its subsidiaries granted the lenders a security interest in substantially all of their personal property, rights and assets as collateral for the Sustainability-Linked Term Loan under the Riverstone Credit Agreement. The Company and certain of its subsidiaries also agreed to grant a security interest in certain of their material real property interests.

The Riverstone Credit Agreement contains customary representations, warranties, and affirmative and negative covenants, including compliance with certain financial ratios and liquidity test and limitation on the Company’s ability to incur additional indebtedness, make certain payments, and enter into certain transactions. Additionally, the Riverstone Credit Agreement includes a number of events of default clauses. If any event of default occurs (subject, in certain instances, to specified grace periods), the then outstanding principal, premium, if any, interest and any other monetary obligations under the Riverstone Credit Agreement may become due and payable immediately.

Other Debt

In May 2023, the Company entered into a sale and leaseback arrangement and received $0.3 million pursuant to the arrangement. The transaction did not qualify for sale and leaseback accounting due to a fixed price repurchase option

that is not at fair value. As a result, the transaction was recorded under the financing method in which the assets remained on the accompanying condensed consolidated balance sheets, and the proceeds from the transaction were recorded as a financing liability. The sale and leaseback arrangement has a term of five years with interest and principal payable in 60 monthly installments at an annual effective rate of 13.38%. As of December 31, 2022 and June 30, 2023, the Company had other outstanding debt bearing interest at 4.75% and 13.38%, respectively.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 470
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//470/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1C

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1E
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1E

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1I
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2023

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Schedule of fair value inputs

The Company estimated the fair value of its outstanding commodity swap contracts based on the following inputs as of December 31, 2022 and June 30, 2023:


	December 31, 2022			June 30, 2023
Significant Unobservable Inputs	Input Range	Weighted Average		Input Range	Weighted Average
ULSD Gulf Coast Forward Curve	$2.35 - $2.59	$	2.48	$1.98 - $2.23	$	2.13
Historical Differential to PADD 3 Diesel	$0.88 - $1.62	$	1.13	$0.92 - $1.62	$	1.14
Historical Differential to PADD 5 Diesel	$1.89 - $3.00	$	2.30	$1.89 - $3.02	$	2.36


	December 31, 2022			June 30, 2023
Significant Unobservable Inputs	Input Range	Weighted Average		Input Range	Weighted Average
ULSD Gulf Coast Forward Curve	$2.35 - $2.59	$	2.48	$1.98 - $2.23	$	2.13
Historical Differential to PADD 3 Diesel	$0.88 - $1.62	$	1.13	$0.92 - $1.62	$	1.14
Historical Differential to PADD 5 Diesel	$1.91 - $3.05	$	2.31	$1.89 - $3.02	$	2.36

Schedule of information by level for assets and liabilities that are measured at fair value on a recurring basis

The following tables provide information by level for assets and liabilities that are measured at fair value on a recurring basis as of December 31, 2022 and June 30, 2023 (in thousands):


	December 31, 2022		Level 1		Level 2		Level 3
Assets:
Available-for-sale securities:
U.S. government securities ⁽¹⁾	$	64,880	$	64,880	$	—	$	—
Zero coupon bonds ⁽¹⁾		74,159		—		74,159		—
Convertible promissory note ⁽⁴⁾		1,880		—		—		1,880
Certificates of deposit ⁽¹⁾		530		—		530		—
Embedded derivatives ⁽³⁾		6,755		—		—		6,755
Liabilities:
Commodity swap contracts ⁽²⁾	$	3,845	$	—	$	—	$	3,845


	June 30, 2023		Level 1		Level 2		Level 3
Assets:
Available-for-sale securities:
U.S. government securities ⁽¹⁾	$	138,039	$	138,039	$	—	$	—
Convertible promissory note ⁽⁴⁾		4,295		—		—		4,295
Certificates of deposit ⁽¹⁾		530		—		530		—
Embedded derivatives ⁽³⁾		6,837		—		—		6,837
Liabilities:
Embedded derivatives ⁽³⁾		80		—		—		80
Commodity swap contracts ⁽²⁾	$	2,779	$	—	$	—	$	2,779

(1)	Included in “Short-term investments” in the accompanying condensed consolidated balance sheets. See Note 5 for more information.

(2)	Included in “Derivative liabilities, related party” and “Long-term portion of derivative liabilities, related party” as of December 31, 2022 and in “Derivative liabilities, related party” as of June 30, 2023 in the accompanying condensed consolidated balance sheets. See Note 6 for more information.

(3)

(4)	Included in “Notes receivable and other long-term assets, net” as of December 31, 2022 and in “Other receivables” as of June 30, 2023 in the accompanying condensed consolidated balance sheets.

Schedule of reconciliation of the beginning and ending balances of items measured at fair value on a recurring basis that used significant unobservable inputs (Level 3)


	Assets:		Assets:		Assets:		Liabilities:		Liabilities:
	Commodity		Embedded		Convertible		Commodity		Embedded
	Swap Contracts		Derivatives		Promissory Note		Swap Contracts		Derivatives
Balance as of March 31, 2022	$	—	$	9,923	$	—	$	(8,566)	$	—
Settlements, net		—		—		—		2,622		—
Total gain (loss)		—		1,422		—		(5,090)		(32)
Balance as of June 30, 2022	$	—	$	11,345	$	—	$	(11,034)	$	(32)

Balance as of March 31, 2023	$	—	$	4,949	$	3,048	$	(3,875)	$	(696)
Settlements, net		—		—		—		1,441		—
Total gain (loss)		—		1,888		889		(345)		616
Purchases		—		—		1,268		—		—
Equity method investment loss		—		—		(910)		—		—
Balance as of June 30, 2023	$	—	$	6,837	$	4,295	$	(2,779)	$	(80)

Change in unrealized gain (loss) for the three months ended June 30, 2022 included in earnings	$	—	$	1,422	$	—	$	(2,468)	$	(32)
Change in unrealized gain (loss) for the three months ended June 30, 2023 included in earnings	$	—	$	1,888	$	—	$	1,096	$	616
Change in unrealized gain (loss) for the three months ended June 30, 2023 included in other comprehensive income (loss)	$	—	$	—	$	889	$	—	$	—


	Assets:		Assets:		Assets:		Liabilities:		Liabilities:
	Commodity		Embedded		Convertible		Commodity		Embedded
	Swap Contracts		Derivatives		Promissory Note		Swap Contracts		Derivatives
Balance as of December 31, 2021	$	—	$	6,776	$	—	$	(4,383)	$	—
Settlements, net		—		—		—		3,901		—
Total gain (loss)		—		4,569		—		(10,552)		(32)
Balance as of June 30, 2022	$	—	$	11,345	$	—	$	(11,034)	$	(32)

Balance as of December 31, 2022	$	—	$	6,755	$	1,880	$	(3,845)	$	—
Settlements, net		(1,424)		—		—		2,456		—
Total gain (loss)		1,424		82		1,105		(1,390)		(80)
Purchases		—		—		2,478		—		—
Equity method investment loss		—		—		(1,168)		—		—
Balance as of June 30, 2023	$	—	$	6,837	$	4,295	$	(2,779)	$	(80)

Change in unrealized gain (loss) for the six months ended June 30, 2022 included in earnings	$	—	$	4,569	$	—	$	(6,651)	$	(32)
Change in unrealized gain (loss) for the six months ended June 30, 2023 included in earnings	$	—	$	82	$	—	$	1,066	$	(80)
Change in unrealized gain (loss) for the six months ended June 30, 2023 included in other comprehensive income (loss)	$	—	$	—	$	1,105	$	—	$	—

Convertible promissory note

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Schedule of fair value inputs

The following table provides quantitative information about the significant inputs used to estimate the fair value of the convertible promissory note as of December 31, 2022 and June 30, 2023:



Significant Unobservable Inputs	December 31, 2022	June 30, 2023
Risk-free interest rate	4.57%	5.42%
Credit adjustment	8.36%	6.80%
Credit adjusted discount rate	12.93%	12.22%

Fair Value Measurements - Fair Value Recognition - Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Reconciliation of the beginning and ending balances of liabilities measured at fair value using significant unobservable inputs (Level 3)
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income [Extensible List]	Revenue from Contract with Customer, Excluding Assessed Tax		Revenue from Contract with Customer, Excluding Assessed Tax
Commodity swap contracts
Reconciliation of the beginning and ending balances of liabilities measured at fair value using significant unobservable inputs (Level 3)
Beginning Balance	$ (3,875)	$ (8,566)	$ (3,845)	$ (4,383)
Settlements, net	1,441	2,622	2,456	3,901
Total gain (loss)	(345)	(5,090)	$ (1,390)	$ (10,552)
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Revenue from Contract with Customer, Excluding Assessed Tax	Revenue from Contract with Customer, Excluding Assessed Tax
Ending Balance	(2,779)	(11,034)	$ (2,779)	$ (11,034)
Change in unrealized gain (loss) included in earnings	1,096	(2,468)	1,066	(6,651)
Embedded derivatives
Reconciliation of the beginning and ending balances of liabilities measured at fair value using significant unobservable inputs (Level 3)
Beginning Balance	(696)
Total gain (loss)	616	(32)	(80)	(32)
Ending Balance	(80)	(32)	(80)	(32)
Change in unrealized gain (loss) included in earnings	$ 616	$ (32)	$ (80)	$ (32)

Land, Property and Equipment

6 Months Ended

Jun. 30, 2023

Property, Plant and Equipment [Abstract]

Land, Property and Equipment

Note 10—Land, Property and Equipment

Land, property and equipment, net as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Land	$	3,476	$	3,620
LNG liquefaction plants		94,790		96,607
Station equipment		353,104		379,272
Trailers		73,253		72,553
Other equipment		106,184		99,795
Construction in progress		91,105		117,921
		721,912		769,768
Less accumulated depreciation		(457,844)		(477,305)
Total land, property and equipment, net	$	264,068	$	292,463

Included in “Land, property and equipment, net” are capitalized software costs of $35.3 million and $35.8 million as of December 31, 2022 and June 30, 2023, respectively. Accumulated amortization of the capitalized software costs are $32.1 million and $33.0 million as of December 31, 2022 and June 30, 2023, respectively.

The Company recorded amortization expense related to capitalized software costs of $0.3 million and $0.5 million in the three months ended June 30, 2022 and 2023, respectively, and $0.6 million and $0.9 million in the six months ended June 30, 2022 and 2023, respectively.

As of December 31, 2022 and June 30, 2023, $12.9 million and $12.7 million, respectively, are included in “Accounts payable” and “Accrued liabilities” in the accompanying condensed consolidated balance sheets, representing

amounts related to purchases of property and equipment. These amounts are excluded from the accompanying condensed consolidated statements of cash flows as they are non-cash investing activities.

Fueling Station Equipment Removal

The Company was requested by Pilot Travel Centers LLC (“Pilot”) to remove station equipment at select Pilot locations to accommodate Pilot making physical changes to the premises, which required the removal of the Company’s station equipment. The premises where the affected fueling stations are located were secured by long-term lease agreements between Pilot and the Company pursuant to which the Company had contractual rights to operate its fueling stations until the expiration of the respective leases. However, in July 2022, the Company entered into an amendment (the “Amendment”) to the Liquefied Natural Gas Fueling Station and LNG Master Sales Agreement between Pilot and Clean Energy, dated August 2, 2010, to decommission and remove station equipment from the premises where the affected fueling stations are located in accordance with a phased removal schedule beginning in the third quarter of 2022. In April 2023, Pilot and the Company agreed to extend the removal completion deadline to provide the Company additional time to obtain the required permits and to complete the decommissioning activities. As of June 30, 2023, removal and decommissioning activities were in progress at two remaining Pilot locations.

Commitments and Contingencies

6 Months Ended

Jun. 30, 2023

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Note 17—Commitments and Contingencies

Environmental Matters

The Company is subject to federal, state, local and foreign environmental laws and regulations. The Company does not anticipate any expenditures to comply with such laws and regulations that would have a material effect on the Company’s consolidated financial position, results of operations or liquidity. The Company believes that its operations comply, in all material respects, with applicable federal, state, local and foreign environmental laws and regulations.

Litigation, Claims and Contingencies

The Company may become party to various legal actions that arise in the ordinary course of its business. The Company is also subject to audit by tax and other authorities for varying periods in various federal, state, local and foreign jurisdictions, and disputes may arise during the course of these audits. It is impossible to determine the ultimate liabilities that the Company may incur resulting from any of these lawsuits, claims, proceedings, audits, commitments, contingencies and related matters or the timing of these liabilities, if any. If these matters were to ultimately be resolved unfavorably, it is possible that such an outcome could have a material adverse effect upon the Company’s consolidated financial position, results of operations, or liquidity. The Company does not, however, anticipate such an outcome and believes the ultimate resolution of these matters will not have a material adverse effect on the Company’s consolidated financial position, results of operations, or liquidity.

Long-Term Take-or-Pay Natural Gas Purchase Contracts

The Company has entered into quarterly fixed price natural gas purchase contracts with take-or-pay commitments extending through June 2024. As of June 30, 2023, the fixed commitments under these contracts totaled approximately $1.7 million for the remainder of the year ending December 31, 2023 and $2.0 million for the year ending December 31, 2024.

Loan Commitment to an Equity Method Investee

In November 2022, the Company entered into a Note Purchase Agreement with a certain equity method investee. Pursuant to the Note Purchase Agreement, the Company irrevocably committed to make available up to $5.5 million in delayed draw loans to fund the investee’s working capital requirements. In exchange, the Company received a convertible promissory note with a principal balance equal to the total amount of drawdown on the loan commitment. The convertible promissory note carries an interest rate equal to 7% per annum, compounded quarterly, and is due and payable in May 2024, subject to certain, specified prepayment clauses.

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Net loss	$ (16,486)	$ (13,362)	$ (55,318)	$ (37,938)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of $0 tax in 2022 and 2023	585	(1,297)	1,046	(1,025)
Unrealized gain (loss) on available-for-sale securities, net of $0 tax in 2022 and 2023	1,113	(119)	1,357	(142)
Total other comprehensive income (loss)	1,698	(1,416)	2,403	(1,167)
Comprehensive loss	(14,788)	(14,778)	(52,915)	(39,105)
Clean Energy Fuels Corp.
Net loss	(16,301)	(13,235)	(54,998)	(37,426)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of $0 tax in 2022 and 2023	585	(1,297)	1,046	(1,025)
Unrealized gain (loss) on available-for-sale securities, net of $0 tax in 2022 and 2023	1,113	(119)	1,357	(142)
Total other comprehensive income (loss)	1,698	(1,416)	2,403	(1,167)
Comprehensive loss	(14,603)	(14,651)	(52,595)	(38,593)
Noncontrolling Interest in Subsidiary
Net loss	(185)	(127)	(320)	(512)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of $0 tax in 2022 and 2023	0	0	0	0
Unrealized gain (loss) on available-for-sale securities, net of $0 tax in 2022 and 2023	0	0	0	0
Total other comprehensive income (loss)	0	0	0	0
Comprehensive loss	$ (185)	$ (127)	$ (320)	$ (512)

- Definition

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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+ Details

Insider Trading Arrangements - Andrew Littlefair Trading Plan - Andrew J. Littlefair	3 Months Ended
	Jun. 30, 2023 shares
Trading Arrangements, by Individual
Material Terms of Trading Arrangement	Rule 10b5-1 Plan Elections. On August 12, 2022, Andrew J. Littlefair, Chief Executive Officer, adopted a Rule 10b5-1 trading plan for the purpose of establishing a sales plan of the Company’s common stock that is intended to comply with the requirements of Rule 10b5-1(c)(1) under the Securities Exchange Act of 1934, as amended. Mr. Littlefair’s Rule 10b5-1 trading plan is in effect from November 13, 2022 to the earlier of (1) November 1, 2023 and (2) the date on which an aggregate of 500,000 shares of the Company’s common stock have been sold pursuant to the Rule 10b5-1 trading plan.
Name	Andrew J. Littlefair
Title	Chief Executive Officer
Rule 10b5-1 Arrangement Adopted	true
Non-Rule 10b5-1 Arrangement Adopted	true
Adoption Date	August 12, 2022
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Aggregate Available	500,000

Land, Property and Equipment - Fueling Station Equipment Removal (Details)	Jun. 30, 2023 location
Property, Plant and Equipment [Abstract]
Number of pilot locations for removal and decommissioning activities in progress	2

Income Taxes

6 Months Ended

Jun. 30, 2023

Income Tax Disclosure [Abstract]

Income Taxes

Note 16—Income Taxes

The provision for income taxes for interim periods is determined using an estimate of the Company’s annual effective tax rate, adjusted for discrete items, if any, that are taken into account in the relevant period. Each quarter, the Company updates the estimate of the annual effective tax rate, and if the estimated tax rate changes, a cumulative adjustment is recorded.

The Company recorded an income tax expense of $0.1 million in the three months ended June 30, 2022 and an income tax benefit of $0.1 million in the three months ended June 30, 2023. The Company recorded an income tax expense of $0.1 million in the six months ended June 30, 2022 and an income tax benefit of $0.1 million in the six months ended June 30, 2023. Income tax expense in both periods are related to the Company’s U.S. and foreign operations. The effective tax rates for the three and six months ended June 30, 2022 and 2023 are different from the federal statutory tax rate primarily due to losses for which no tax benefit has been recognized.

The Company increased its unrecognized tax benefits in the six months ended June 30, 2023 by $2.3 million. This increase is primarily attributable to the portion of AFTC revenue recognized in the period attributed to the federal fuel tax the Company collected from its customers and deductions attributed to the unvested Amazon Warrant during the six months ended June 30, 2023. The net interest incurred was immaterial for the three and six months ended June 30, 2022 and 2023.

On August 16, 2022, the Inflation Reduction Act of 2022 (the “IRA”) was signed into law. The IRA offers significant tax incentives targeting energy transaction and renewables:

●

Alternative Fuel Tax Credit (“AFTC”) is reinstated to apply retroactively to fuel sales transactions from January 1, 2022 through December 31, 2024.

●

The investment tax credit under Section 48 of the Internal Revenue Code is expanded to include Qualified Biogas Property placed in service after December 31, 2022. The rate of this credit is 6% at base level and increased to 30% if the prevailing wages and apprenticeship requirements are met. Further, this credit is transferrable to an unrelated party. The Company expects the credit to bring significant cash flow for the Renewable Natural Gas projects that it has invested and will invest through year 2024.

●

A new tax credit under Section 45Z of the Internal Revenue Code is introduced to apply to transportation fuel produced and sold by the taxpayer from January 1, 2025 through December 31, 2027. The bonus credit is $1.00/gallon multiplied by an applicable emissions factor but would be reduced to $0.20/gallon ($0.35/gallon for sustainable aviation fuel) if prevailing wage and apprenticeship requirements are not met. Given the negative carbon intensity (“CI”) score for renewable natural gas, the Company expects that the Renewable Natural Gas projects will be eligible for this credit at a rate greater than $1.00/gallon of fuel sold.

●

The alternative fuel refueling property credit under Section 30C of the Internal Revenue Code was reinstated for 2022 and extended an additional 10 years to apply to any property placed in service before January 1, 2033. For business property, the credit amount decreases to 6% (from 30%) with a maximum amount of $100,000 per item (previously $30,000 per location per year). Business property meeting prevailing wage and registered apprenticeship requirements may be eligible for a credit amount of 30% ($100,000 maximum).

The Internal Revenue Service and Treasury have been issuing regulations or other guidance that clarify how these credits will be eligible and calculated. The Company will continue to evaluate the impact of the IRA as additional information becomes available.

- Definition

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+ Details

Debt - Other Debt (Details) $ in Millions	May 31, 2023 USD ($) installment	Jun. 30, 2023	Dec. 31, 2022	Nov. 07, 2022
Long-term debt [Line Items]
Interest rate				7.00%
Other debt
Long-term debt [Line Items]
Interest rate		13.38%	4.75%
Other debt \| Sale and leaseback arrangement
Long-term debt [Line Items]
Proceeds from sale of equipment in sale-leaseback agreement \| $	$ 0.3
Number of equal monthly installments \| installment	60
Sale leaseback transaction, term	5 years
Annual rate (as a percent)	13.38%

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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+ Details

Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2023	Aug. 02, 2023
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2023
Document Fiscal Year Focus	2023
Securities Act File Number	001-33480
Entity Registrant Name	CLEAN ENERGY FUELS CORP.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	33-0968580
Entity Address, Address Line One	4675 MacArthur Court
Entity Address, Address Line Two	Suite 800
Entity Address, City or Town	Newport Beach
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92660
City Area Code	949
Local Phone Number	437-1000
Title of 12(b) Security	Common stock, $0.0001 par value per share
Trading Symbol	CLNE
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		222,966,819
Entity Central Index Key	0001368265
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q2
Amendment Flag	false

Stockholders' Equity - Share Repurchase Program (Details) - USD ($) $ in Thousands	3 Months Ended		40 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Dec. 07, 2021	Dec. 06, 2021	Mar. 12, 2020
Stockholders' Equity Note [Abstract]
Approved share repurchase program				$ 50,000	$ 30,000	$ 30,000
Cost to repurchase common stock	$ 3,121	$ 3,001
Stock repurchase program total stock repurchased			9,387,340
Amount utilized under the repurchase plan			$ 23,500
Authorized funds remaining under the Repurchase Program			$ 26,500

- Definition

Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References + Details

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 1,501	$ 1,375
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, authorized (in shares)	1,000,000	1,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, authorized (in shares)	454,000,000	454,000,000
Common stock, issued (in shares)	222,910,057	222,437,429
Common stock, outstanding (in shares)	222,910,057	222,437,429

Short-Term Investments (Tables)

6 Months Ended

Jun. 30, 2023

Investments, Debt and Equity Securities [Abstract]

Summary of short-term investments

Short-term investments as of December 31, 2022 consisted of the following (in thousands):


			Gross
	Amortized		Unrealized		Estimated
	Cost		Gain (Loss)		Fair Value
Zero coupon bonds	$	74,524	$	(365)	$	74,159
U.S. government securities		64,861		19		64,880
Certificates of deposit		530		—		530
Total short-term investments	$	139,915	$	(346)	$	139,569

Short-term investments as of June 30, 2023 consisted of the following (in thousands):


			Gross
	Amortized		Unrealized		Estimated
	Cost		Gain (Loss)		Fair Value
U.S. government securities	$	137,999	$	40	$	138,039
Certificates of deposit		530		—		530
Total short-term investments	$	138,529	$	40	$	138,569

Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
Stock-Based Compensation (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based compensation expense, net of $0 tax in 2022 and 2023	$ 6,093	$ 6,468	$ 12,189	$ 14,721
Stock-based compensation expense, tax	0	$ 0	0	$ 0
Unrecognized compensation cost	23,000		$ 23,000
Unrecognized compensation cost, weighted-average period			1 year 6 months
Total unrecognized compensation cost related to non-vested shares	$ 4,200		$ 4,200

Revenue from Contracts with Customers - Contract Balances (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Revenue from Contract with Customer [Abstract]
Accounts receivable, net	$ 74,746	$ 91,430
Contract assets - current	8,724	6,063
Contract assets - non-current	2,699	2,976
Contract assets - total	11,423	9,039
Contract liabilities - current	3,329	5,477
Contract liabilities - non-current	0	0
Contract liabilities - total	$ 3,329	$ 5,477

Investments in Other Entities and Noncontrolling Interest in a Subsidiary - NG Advantage (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022	Oct. 14, 2014
Schedule of Equity Method Investments [Line Items]
Loss from noncontrolling interest	$ (185)	$ (127)	$ (320)	$ (512)
Investments carried at cost	8,000		8,000
NG Advantage \| NG Advantage
Schedule of Equity Method Investments [Line Items]
Noncontrolling interest, fair value	7,200		7,200		$ 7,500
NG Advantage \| NG Advantage
Schedule of Equity Method Investments [Line Items]
Loss from noncontrolling interest			$ 300	$ 500
NG Advantage \| NG Advantage \| NG Advantage
Schedule of Equity Method Investments [Line Items]
Loss from noncontrolling interest	$ 200	$ 100
NG Advantage \| Common unit purchase agreement
Schedule of Equity Method Investments [Line Items]
Ownership interest acquired						53.30%
Ownership interest after transaction (as a percent)			93.30%

Other Receivables

6 Months Ended

Jun. 30, 2023

Receivables [Abstract]

Other Receivables

Note 8—Other Receivables

Other receivables as of December 31, 2022 and June 30, 2023 consisted of the following (in thousands):


	December 31,		June 30,
	2022		2023
Loans to customers to finance vehicle purchases	$	523	$	422
Accrued customer billings		4,910		7,489
Fuel tax credits		9,462		7,376
Other		2,131		11,801
Total other receivables	$	17,026	$	27,088

Fair Value Measurements - Commodity Swap Contracts (Details) - Not Designated as Hedging Instrument - Valuation Technique, Discounted Cash Flow - Level 3	Jun. 30, 2023	Dec. 31, 2022
Commodity swaps \| Minimum \| ULSD Gulf Coast Forward Curve
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.98	2.35
Commodity swaps \| Minimum \| Historical Differential to PADD 3 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.92	0.88
Commodity swaps \| Minimum \| Historical Differential to PADD 5 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.89	1.89
Commodity swaps \| Maximum \| ULSD Gulf Coast Forward Curve
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	2.23	2.59
Commodity swaps \| Maximum \| Historical Differential to PADD 3 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.62	1.62
Commodity swaps \| Maximum \| Historical Differential to PADD 5 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	3.02	3.00
Commodity swaps \| Weighted Average \| ULSD Gulf Coast Forward Curve
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	2.13	2.48
Commodity swaps \| Weighted Average \| Historical Differential to PADD 3 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.14	1.13
Commodity swaps \| Weighted Average \| Historical Differential to PADD 5 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	2.36	2.30
Fueling agreements \| Minimum \| ULSD Gulf Coast Forward Curve
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.98	2.35
Fueling agreements \| Minimum \| Historical Differential to PADD 3 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	0.92	0.88
Fueling agreements \| Minimum \| Historical Differential to PADD 5 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.89	1.91
Fueling agreements \| Maximum \| ULSD Gulf Coast Forward Curve
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	2.23	2.59
Fueling agreements \| Maximum \| Historical Differential to PADD 3 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.62	1.62
Fueling agreements \| Maximum \| Historical Differential to PADD 5 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	3.02	3.05
Fueling agreements \| Weighted Average \| ULSD Gulf Coast Forward Curve
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	2.13	2.48
Fueling agreements \| Weighted Average \| Historical Differential to PADD 3 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	1.14	1.13
Fueling agreements \| Weighted Average \| Historical Differential to PADD 5 Diesel
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Derivative asset, measurement input	2.36	2.31