CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities
Net income (loss)	$ 1,463	$ (40,219)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Deferred income taxes	394	(3,054)
Gain on extinguishment of debt	(10,000)
Depreciation and amortization of property, plant and equipment	51,380	51,957
Amortization of intangible and other assets	944	946
Stock-based compensation	4,328	1,626
Other	3,184	3,630
Cash provided (used) by changes in assets and liabilities:
Accounts receivable	(22,130)	(1,860)
Inventories	1,637	3,661
Prepaid insurance	10,436	10,359
Accounts payable	9,432	(11,269)
Accrued interest	10,321	12,083
Accrued payroll and benefits	9,938	1,434
Other assets and other liabilities	(5,856)	(4,579)
Net cash provided by operating activities	65,471	24,715
Cash flows from investing activities
Expenditures for property, plant and equipment	(26,101)	(22,230)
Proceeds from vendor settlements associated with property, plant and equipment		1,647
Other investing activities	382	364
Net cash used by investing activities	(25,719)	(20,219)
Cash flows from financing activities
Proceeds from revolving debt facility	12,000	30,000
Payments on revolving debt facility	(12,000)	(30,000)
Proceeds from other long-term debt		42,570
Payments on other long-term debt	(7,726)	(18,397)
Payments of debt-related costs	(611)	(124)
Payments on short-term financing	(12,493)	(9,178)
Payments of costs to exchange redeemable preferred stocks for common stock	(2,076)
Other financing activities	(255)	(64)
Net cash provided (used) by financing activities	(23,161)	14,807
Net increase in cash and cash equivalents	16,591	19,303
Cash and cash equivalents at beginning of period	16,264	22,791
Cash and cash equivalents at end of period	$ 32,855	$ 42,094