Supplemental Guarantor Information (Consolidating Statements of Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Condensed Financial Statements, Captions [Line Items]
Net loss	$ (98,524)	$ (38,442)	$ (71,050)	$ (47,705)	$ (750,185)	$ (21,816)	$ (26,390)	$ (59,724)	$ (255,721)	$ (858,115)	$ (205,921)
Change in cumulative translation adjustment, net of tax									1,250	(5,750)	12,821
Comprehensive loss									(254,471)	(863,865)	(193,100)
Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss									360,156	1,566,060	283,279
Change in cumulative translation adjustment, net of tax									(2,500)	11,500	(25,642)
Comprehensive loss									357,656	1,577,560	257,637
Parent [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss									(255,721)	(858,115)	(205,921)
Change in cumulative translation adjustment, net of tax									1,250	(5,750)	12,821
Comprehensive loss									(254,471)	(863,865)	(193,100)
Issuer [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss									(255,721)	(858,115)	(205,921)
Change in cumulative translation adjustment, net of tax									1,250	(5,750)	12,821
Comprehensive loss									(254,471)	(863,865)	(193,100)
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss									(125,514)	(596,718)	(7,163)
Comprehensive loss									(125,514)	(596,718)	(7,163)
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net loss									21,079	(111,227)	(70,195)
Change in cumulative translation adjustment, net of tax									1,250	(5,750)	12,821
Comprehensive loss									$ 22,329	$ (116,977)	$ (57,374)