Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Dec. 31, 2018	Nov. 19, 2018	Dec. 31, 2019	Dec. 31, 2017
Revenues
Contract drilling	$ 28,489	$ 236,379	$ 229,777	$ 319,716
Revenue, Product and Service [Extensible List]	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember	us-gaap:OilAndGasServiceMember
Costs and expenses
Operating expenses	$ 19,744	$ 189,606	$ 228,143	$ 244,089
General and administrative expenses	4,245	50,604	38,293	87,134
Depreciation and amortization expense	27,277	248,302	193,128	278,949
Loss from unconsolidated subsidiaries	806		220,152
Total costs and expenses	52,072	488,512	679,716	610,172
Operating loss	(23,583)	(252,133)	(449,939)	(290,456)
Other income (expense)
Interest expense	(10,904)	(106,632)	(97,698)	(178,983)
Write-off of deferred financing costs				(30,846)
Reorganization items	(1,300)	(1,799,664)	(1,975)	(6,474)
Interest income	1,008	3,148	6,292	2,717
Other income (expense)	526	(1,904)	(729)	(8,261)
Loss before income taxes	(34,253)	(2,157,185)	(544,049)	(512,303)
Income tax expense (benefit)	(6,769)	(2,308)	12,416	12,863
Net loss	$ (27,484)	$ (2,154,877)	$ (556,465)	$ (525,166)
Loss per common share, basic (in dollars per share)	$ (0.37)	$ (100.89)	$ (7.42)	$ (24.64)
Weighted-average shares outstanding, basic	75,010	21,359	75,011	21,315
Loss per common share, diluted (in dollars per share)	$ (0.37)	$ (100.89)	$ (7.42)	$ (24.64)
Weighted-average shares outstanding, diluted	75,010	21,359	75,011	21,315