Debt - SG Credit and TOTAL Credit Support Agreement (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Jan. 02, 2019	Mar. 31, 2022	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Mar. 12, 2021
Long-term debt [Line Items]
Outstanding amount			$ 32,528		$ 36,132
Proceeds from revolving line of credit			0	$ 1,150
Term Loan Facility | Socit Gnrale
Long-term debt [Line Items]
Maximum borrowing capacity (up to)	$ 100,000
Commitment fee percentage	0.39%
Quarterly principal payments		$ 2,500
Covenant for debt default	$ 20,000
Outstanding amount			$ 4,500
Term Loan Facility | Socit Gnrale | London Interbank Offered Rate (LIBOR)
Long-term debt [Line Items]
Basis spread on variable rate	1.30%
Term Loan Facility | Socit Gnrale | Station Build Costs
Long-term debt [Line Items]
Maximum borrowing capacity (up to)						$ 45,000
Term Loan Facility | Socit Gnrale | ADG RNG Production Facilities
Long-term debt [Line Items]
Maximum borrowing capacity (up to)						$ 20,000
Term Loan Facility | Total Holdings USA Inc.
Long-term debt [Line Items]
Maximum borrowing capacity (up to)	$ 100,000
Interest rate per quarter	2.50%
Covenant for debt default	$ 20,000
Term Loan Facility | Total Holdings USA Inc. | London Interbank Offered Rate (LIBOR)
Long-term debt [Line Items]
Basis spread on variable rate	1.00%