Voluntary Reorganization under Chapter 11 - Condensed Cash Flow Statement of Debtors-in-Possession (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Cash Flow Statements, Captions [Line Items]
Net cash used in operating activities	$ (47,336)	$ 152,962	$ 144,799
Cash flows from investing activities:
Payments for property, plant and equipment	(89,402)	(115,367)	(106,726)
Proceeds from sale of fixed assets	5,987	19,467	4,336
Net cash used in investing activities	(83,415)	(109,224)	(134,986)
Cash flows from financing activities:
Repayments of debt	(1,834)	(1,053)	(143,323)
Payments of financing costs	(40,627)	(715)	(1,786)
Proceeds from DIP senior credit facility	70,000	0	0
Proceeds from senior secured revolver	1,294,501	351,800	326,900
Payments for senior secured revolver	(1,125,001)	(343,700)	(324,800)
Issuance of common stock, net of share repurchases for withholding taxes	(425)	(445)	(535)
Net cash provided by financing activities	186,586	(36,074)	(11,281)
Increase (decrease) in cash and cash equivalents	55,835	7,664	(1,468)
Cash and cash equivalents, beginning of year	24,176	16,512	17,980
Cash and cash equivalents, end of year	80,011	24,176	$ 16,512
Debtors-in-Possession
Condensed Cash Flow Statements, Captions [Line Items]
Net cash used in operating activities	(56,259)
Cash flows from investing activities:
Payments for property, plant and equipment	(89,402)
Proceeds from sale of fixed assets	5,987
Net cash used in investing activities	(83,415)
Cash flows from financing activities:
Repayments of debt	(1,834)
Payments of financing costs	(40,627)
Proceeds from DIP senior credit facility	70,000
Proceeds from senior secured revolver	1,294,501
Payments for senior secured revolver	(1,125,001)
Intercompany loans	(1,250)
Issuance of common stock, net of share repurchases for withholding taxes	(425)
Net cash provided by financing activities	195,364
Increase (decrease) in cash and cash equivalents	55,690
Cash and cash equivalents, beginning of year	17,473
Cash and cash equivalents, end of year	$ 73,163	$ 17,473

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