Schedule I Financial Information - Schedule of Reorganization Items and Fresh Start Accounting Adjustments (Details) - USD ($) $ in Thousands	1 Months Ended	2 Months Ended	3 Months Ended	11 Months Ended	12 Months Ended
	Feb. 09, 2018	Mar. 31, 2018	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Reorganization Items [Line Items]
Gain on cancellation of corporate debt	$ 556,937			$ 0	$ 0
Issuance of new equity to Convertible and Senior Noteholders	153,764			0	0
Net gain on cancellation of corporate debt	403,173			0	0
Less:
Legal and professional fees	12,461			2,123	3,098
Write-off deferred debt issuance costs and discounts	0			0	34,406
Other expenses	3,378			603	141
Total expenses	15,839			2,726	37,645
Total reorganization items	387,334			(2,726)	(37,645)
Fresh start accounting adjustments	77,229			0	0
Reorganization items and fresh start accounting adjustments	464,563	$ (100)	$ (2,600)	(2,726)	(37,645)
Parent Company [Member]
Reorganization Items [Line Items]
Gain on cancellation of corporate debt	556,937			0	0
Issuance of new equity to Convertible and Senior Noteholders	153,764			0	0
Net gain on cancellation of corporate debt	403,173			0	0
Less:
Legal and professional fees	12,461			2,123	3,098
Write-off deferred debt issuance costs and discounts	0			0	34,406
Other expenses	3,378			603	141
Total expenses	15,839			2,726	37,645
Total reorganization items	387,334			(2,726)	(37,645)
Fresh start accounting adjustments	71,177			0	0
Reorganization items and fresh start accounting adjustments	$ 458,511			$ (2,726)	$ (37,645)