Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net income	$ 74,751	$ 14,085
Adjustments to reconcile net income to net cash from operating activities:
Accretion of asset retirement obligations	990	305
Depreciation and amortization	18,463	12,110
Amortization of debt issuance costs	243	29
Stock-based compensation	4,173	2,577
Other income - gain on sale of mineral rights	(2,113)
Other income - employee retention tax credit		(5,316)
Deferred income taxes	6,448	62
Changes in operating assets and liabilities:
Accounts receivable	(8,293)	6,417
Prepaid expenses and other current assets	1,472	4,724
Inventories	(16,597)	(7,628)
Other assets and liabilities	1,263	(258)
Accounts payable	10,060	4,562
Accrued expenses	18,441	1,253
Net cash from operating activities	109,301	32,922
Cash flow from investing activities:
Capital expenditures	(53,807)	(8,551)
Acquisition of Ramaco Coal assets	(11,738)
Proceeds from sale of mineral rights	2,000
Net cash from investing activities	(63,545)	(8,551)
Cash flows from financing activities:
Proceeds from borrowings	1,337	14,100
Payment of dividends	(9,996)
Repayment of borrowings	(9,407)	(23,523)
Repayments of financed insurance payable	(210)	(751)
Repayments of financing leased equipment	(2,718)	(409)
Restricted stock surrendered for withholding taxes payable	(2,821)	(327)
Net cash from financing activities	(23,815)	(10,910)
Net change in cash and cash equivalents and restricted cash	21,941	13,461
Cash and cash equivalents and restricted cash, beginning of period	22,806	6,710
Cash and cash equivalents and restricted cash, end of period	44,747	20,171
Supplemental cash flow information:
Cash paid for interest	2,640	419
Cash paid for taxes	13,000
Non-cash investing and financing activities:
Leased assets obtained under new financing leases	3,624	5,741
Capital expenditures included in accounts payable and accrued expenses	15,609	1,771
Ramaco Coal acquisition	56,551
Additional asset retirement obligations incurred	$ 1,708	$ 145