CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities
Net (loss) income	$ (10,204)	$ 33,270
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Deferred income taxes	(2,880)	2,883
Gain on extinguishment of debt	(3,013)	(8,644)
Depreciation expense on the related plant, property and equipment	52,484	49,852
Amortization of short term investments	4,528	(2,806)
Amortization of intangible and other assets	141	403
Stock-based compensation	5,042	3,964
Provision for impairment on property, plant and equipment	6,785	207
Other	3,966	4,253
Cash provided (used) by changes in assets and liabilities:
Accounts receivable	(3,890)	28,365
Inventories	6,604	6,727
Prepaid insurance	12,832	15,566
Supplies, prepaid items and other	(842)	1,761
Accounts payable	6,995	(12,672)
Accrued interest	3,634	2,237
Accrued payroll and benefits	(961)	(5,489)
Other assets and other liabilities	1,379	645
Net cash provided by operating activities	82,600	120,522
Cash flows from investing activities
Expenditures for property, plant and equipment	(64,087)	(41,123)
Proceeds from short-term investments	236,493	293,347
Purchases of short-term investments	(190,646)	(230,690)
Other investing activities	(140)	(28)
Net cash (used) provided by investing activities	(18,380)	21,506
Cash flows from financing activities
Repurchases of 6.25% Senior Secured Notes	(92,216)	(114,320)
Payments on other long-term debt	(3,986)	(8,155)
Payments on short-term financing	(11,870)	(16,134)
Acquisition of treasury stock, net	(14,208)	(20,364)
Payments of debt-related costs	(689)
Net cash used by financing activities	(122,969)	(158,973)
Net decrease in cash and cash equivalents	(58,749)	(16,945)
Cash, cash equivalents and restricted cash at beginning of period	101,032	63,769
Cash and cash equivalents at end of period	$ 42,283	$ 46,824