Fresh Start Accounting - (Fresh Start) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Feb. 03, 2021	Feb. 02, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 314,974	$ 172,768	$ 172,768	$ 188,006	$ 272,624	$ 158,050
Restricted Cash and Cash Equivalents, Current		16,751	16,751
Accounts receivable, net			153,529
Income taxes receivable			8,976
Prepaid Expense, Current	15,861		31,630	31,793
Inventory and Other Current Assets	60,603		101,140	77,027
Assets held for sale			220,359
Total current assets	648,933		705,153	715,508
Property, plant and equipment, net	356,274		540,850	408,107
Operating lease right-of-use assets			33,918
Goodwill				138,677
Notes receivable			72,484
Restricted Cash and Cash Equivalents, Noncurrent	79,561	$ 80,179	80,179	80,178	2,764	5,698
Finite-Lived Intangible Assets, Net	8,564		24,220	4,996
Total assets	1,199,508		1,456,804	1,501,079
Current liabilities:
Accounts payable	43,080		51,116	50,330
Accrued expenses	116,882		137,216	114,777
Liabilities held for sale	5,607		37,264	46,376
Total current liabilities	165,569		225,596	211,483
Decommissioning liabilities	190,380		169,515	134,436
Operating lease liabilities	19,193		23,555	29,464
Deferred income taxes	12,441		59,522	5,288
Other long-term liabilities	70,192		75,930	123,261
Total non-current liabilities	292,206		328,522	292,449
Liabilities subject to compromise			1,572,772	1,335,794
Total liabilities	457,775		554,118	1,839,726
Stockholders’ equity (deficit):
Treasury Stock at Cost				4,290
Common Stock $0.001 par value			200	16
Additional paid-in capital			902,486
Accumulated other comprehensive loss, net				(67,947)
Accumulated deficit	(162,178)			(3,023,315)
Total stockholders’ equity (deficit)	741,733		902,686	(338,647)	$ 49,573	$ 290,739
Total liabilities and stockholders’ equity (deficit)	1,199,508		1,456,804	$ 1,501,079
Reorganization, Chapter 11, Predecessor, before Adjustment [Member]
Current assets:
Cash and cash equivalents			194,671
Accounts receivable, net			153,518
Income taxes receivable			9,146
Prepaid Expense, Current			31,630
Inventory and Other Current Assets			90,073
Assets held for sale			240,761
Total current assets			719,799
Property, plant and equipment, net			401,263
Operating lease right-of-use assets			32,488
Goodwill			138,934
Notes receivable			72,484
Restricted Cash and Cash Equivalents, Noncurrent			80,179
Finite-Lived Intangible Assets, Net			52,264
Total assets	1,456,800		1,497,411
Current liabilities:
Accounts payable			51,816
Accrued expenses			126,768
Liabilities held for sale			39,642
Total current liabilities			218,226
Decommissioning liabilities			134,934
Operating lease liabilities			23,584
Deferred income taxes			4,853
Other long-term liabilities			121,756
Total non-current liabilities			285,127
Liabilities subject to compromise			1,572,772
Total liabilities	$ 2,076,100		2,076,125
Stockholders’ equity (deficit):
Treasury Stock at Cost			(4,290)
Common Stock $0.001 par value			16
Additional paid-in capital			2,757,824
Accumulated other comprehensive loss, net			(67,532)
Accumulated deficit			(3,264,732)
Total stockholders’ equity (deficit)			(578,714)
Total liabilities and stockholders’ equity (deficit)			1,497,411
Reorganization Adjustments [Member]
Current assets:
Cash and cash equivalents			(21,903)
Restricted Cash and Cash Equivalents, Current			16,751
Accounts receivable, net			11
Total current assets			(5,141)
Finite-Lived Intangible Assets, Net			(10,080)
Total assets			(15,221)
Current liabilities:
Accounts payable			(700)
Accrued expenses			9,042
Liabilities held for sale			1,614
Total current liabilities			9,956
Deferred income taxes			3,100
Total non-current liabilities			3,100
Liabilities subject to compromise			(1,572,772)
Total liabilities			(1,559,716)
Stockholders’ equity (deficit):
common stock $0.001 par value			(16)
Additional paid-in capital			(2,757,824)
Treasury Stock at Cost			4,290
Common Stock $0.001 par value			200
Additional paid-in capital			902,486
Accumulated deficit			3,395,359
Total stockholders’ equity (deficit)			1,544,495
Total liabilities and stockholders’ equity (deficit)			(15,221)
Reorganization, Chapter 11, Fresh-Start Adjustment [Member]
Current assets:
Restricted Cash and Cash Equivalents, Current			16,751
Income taxes receivable			(170)
Inventory and Other Current Assets			11,067
Assets held for sale			(20,402)
Total current assets			(9,505)
Property, plant and equipment, net			139,587
Operating lease right-of-use assets			1,430
Goodwill			(138,934)
Notes receivable
Restricted Cash and Cash Equivalents, Noncurrent
Finite-Lived Intangible Assets, Net			(17,964)
Total assets			(25,386)
Current liabilities:
Accrued expenses			1,406
Liabilities held for sale			(3,992)
Total current liabilities			(2,586)
Decommissioning liabilities			34,581
Operating lease liabilities			(29)
Deferred income taxes			51,569
Other long-term liabilities			(45,826)
Total non-current liabilities			40,295
Total liabilities			37,709
Stockholders’ equity (deficit):
Accumulated other comprehensive loss, net			67,532
Accumulated deficit			(130,627)
Total stockholders’ equity (deficit)			(63,095)
Total liabilities and stockholders’ equity (deficit)			$ (25,386)