Bankruptcy Proceedings, Emergence and Fresh Start Accounting Schedule of Items Included in Reorganization Items, Net (Details) - USD ($) $ in Thousands	8 Months Ended	12 Months Ended
	Sep. 12, 2016	Dec. 31, 2018
Reorganizations [Abstract]
Liabilities subject to compromise, gain	$ 1,150,248	$ 0
Fresh-Start Adjustment, Description	28319	0
Reorganization items, legal and professional fees	$ 29,976	$ 200
Reorganization items, Settlements related to contract amendments	(2,550)	0
Debtor Reorganization Items, DIP Facility Costs and Commitment fees	(170)	0
Reorganization Items, Write-off Prepaid D&O Insurance	(832)	0
Debtor Reorganization Items, Other Expense (Income)	(46)	3,122
Debtor Reorganization Items	$ 1,144,993	3,322
Reorganization Item - Potential Settlement of Certain Claims in Cash		2,700
Reorganization Items - Secured claims-AP		$ 400