CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating activities
Net loss	$ (78,255,000)	$ (136,171,000)	$ (672,397,000)
Adjustments to reconcile net loss to operating cash flows:
Depreciation and amortization	182,022,000	203,958,000	263,819,000
Share-based compensation expense	16,751,000	18,439,000	26,350,000
Non-cash interest expense	21,303,000	25,507,000	24,086,000
Provision (benefit) for deferred income taxes	2,549,000	44,970,000	(30,175,000)
(Gain) loss on sale or disposal of assets, net	(6,883,000)	17,208,000	(5,680,000)
Loss on convertible notes derivative	0	126,600,000	74,329,000
(Gain) loss on early extinguishment of debt	(399,000)	48,708,000	43,760,000
Asset impairments	1,056,000	3,976,000	11,029,000
Goodwill and intangible impairments	0	0	393,446,000
Pension and other postretirement benefit obligations	(80,012,000)	(150,824,000)	(117,522,000)
Change in other assets and liabilities:
Accounts receivables, net	44,943,000	(33,246,000)	111,506,000
Inventory	(7,434,000)	(2,824,000)	19,965,000
Prepaid expenses	3,244,000	5,576,000	4,078,000
Accounts payable and accrued liabilities	(23,653,000)	(33,457,000)	(66,377,000)
Deferred revenue	(30,076,000)	931,000	(19,348,000)
Other assets and liabilities	(4,380,000)	(11,898,000)	(3,099,000)
Cash provided by operating activities	40,776,000	127,453,000	57,770,000
Investing activities
Acquisitions, net of cash acquired	(15,432,000)	(125,000)	0
Purchase of property, plant, and equipment	(45,376,000)	(39,560,000)	(36,975,000)
Proceeds from sale of real estate and other assets	83,504,000	111,765,000	196,344,000
Insurance proceeds received for damage to property	0	0	1,643,000
Change in other investing activities	(572,000)	(1,433,000)	(876,000)
Cash provided by investing activities	22,124,000	70,647,000	160,136,000
Financing activities
Payments of deferred financing costs	(1,652,000)	(21,071,000)	(2,307,000)
Borrowings of long-term debt	80,000,000	1,934,940,000	0
Repayments of long-term debt	(170,994,000)	(2,156,046,000)	(681,050,000)
Repurchase of convertible debt	0	(15,012,000)	0
Proceeds from convertible debt	0	0	497,094,000
Acquisition of noncontrolling interests	(2,050,000)	0	0
Treasury stock	(6,555,000)	(3,244,000)	(2,020,000)
Changes in other financing activities	(1,616,000)	(739,000)	(13,059,000)
Cash used for financing activities	(102,867,000)	(261,172,000)	(201,342,000)
Effect of currency exchange rate change on cash	1,152,000	(35,000)	1,498,000
Increase (decrease) in cash, cash equivalents and restricted cash	(38,815,000)	(63,107,000)	18,062,000
Cash, cash equivalents and restricted cash at beginning of year	143,619,000	206,726,000	188,664,000
Cash, cash equivalents and restricted cash at end of year	$ 104,804,000	$ 143,619,000	$ 206,726,000