Leases, Right-of-Use Assets and Related Liabilities - Narrative (Details) $ in Thousands	Mar. 31, 2022 USD ($) contract site	Dec. 31, 2021 USD ($)
Leases [Abstract]
Operating right-of-use assets	$ 2,209	$ 2,414
Total lease liabilities	2,254
Operating lease liabilities (current)	416	772
Operating lease liabilities (long-term)	$ 1,838	1,902
Number of finance lease | contract	4
Number of digester sites | site	3
Finance right-of-use assets	$ 26,887	27,297
Total lease liabilities	21,432
Finance lease liabilities (current)	4,029	3,413
Finance lease liabilities (long-term)	$ 17,403	$ 17,797