CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Cash flows from operating activities:
Net income	$ 20,229	$ 19,692
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, amortization, and accretion	16,772	12,677
Stock-based compensation	4,858	4,312
Allowance for accounts receivable	2,454	0
Income from equity method investments	(1,877)	(11,828)
Distributions from return on investment in equity method investments	8,059	13,661
Gain on nonmonetary asset	(1,100)	0
Gain on lease termination	(600)	0
Reduction of carrying amount of operating lease right-of-use assets	575	555
Write-offs of capitalized costs	299	0
Amortization of deferred financing costs	1,524	1,310
Paid-in-kind interest income	(156)	(207)
Change in fair value of commodity swaps	(921)	494
Gain on note receivable	(815)	(11)
Unrealized gain on derivative financial instruments	(281)	(1,457)
Changes in operating assets and liabilities
Accounts receivable	(3,536)	(11,986)
Accounts receivable, related party	(7,169)	3,563
Fuel tax credits receivable	2,375	(620)
Contract assets	(1,571)	(2,858)
Parts inventory	(1,788)	(300)
Prepaid expense and other current and long-term assets	8,593	(3,751)
Accounts payable	(1,138)	(775)
Accounts payable, related party	(507)	1,356
Fuel tax credits payable	(1,353)	(34)
Accrued payroll	(969)	(1,053)
Accrued expenses and other current and non-current liabilities	(468)	9,859
Operating lease liabilities - current and non-current	(574)	(517)
Contract liabilities	(898)	(165)
Net cash provided by operating activities	40,017	31,917
Cash flows from investing activities:
Purchase of property, plant, and equipment	(60,890)	(72,805)
Payment for short-term investments	0	(791)
Distributions from return of investment in equity method investment	6,236	1,756
Cash paid to equity method investments	(16,656)	(13,956)
Cash received from (paid for) note receivable	1,377	(750)
Net cash used in investing activities	(69,933)	(86,546)
Cash flows from financing activities:
Proceeds from OPAL Term Loan and Revolving loan	60,000	45,000
Financing costs paid to other third parties	(1,250)	(629)
Repayment of OPAL Revolving Loan	(15,000)	0
Repayment of Sunoma Loan	(1,295)	(1,193)
Repayment of principal portion of finance lease liabilities	(1,144)	(43)
Payment of preferred dividends	(7,852)	(10,469)
Distribution to non-redeemable non-controlling interest	(150)	(628)
Capital contribution from non-redeemable non-controlling interests	1,991	0
Proceeds from issuance of shares of Class A common stock under the ATM program, net	58	170
Cash paid for taxes related to net share settlement of equity awards	(387)	(627)
Net cash provided by financing activities	34,971	31,581
Net increase (decrease) in cash, restricted cash, and cash equivalents	5,055	(23,048)
Cash, restricted cash, and cash equivalents, beginning of period	29,228	47,242
Cash, restricted cash, and cash equivalents, end of period	34,283	24,194
Supplemental disclosure of cash flow information
Interest paid, net of $2,082 and $3,093 capitalized, respectively	20,523	8,628
Tax benefit received	36,290	8,906
Noncash investing and financing activities:
Accrual for asset retirement obligation included in property, plant and equipment	0	499
Right-of-use assets arising from lease modifications	0	1,218
Right-of-use assets for finance leases included in property, plant and equipment	58	0
Accrual for purchase of property, plant and equipment included in accrued and payable capital expenditures	$ 10,014	$ 24,721