Schedule I Financial Information - Statements of Comprehensive Loss (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	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
REVENUES
Interest income on loans	$ 3,387									$ 1,832	$ 41,195
Other revenues, net	16,662									109,231	116,573
Total revenues	187,273	$ 91,215	$ 164,539	$ 204,658	$ 198,528	$ 200,544	$ 176,644	$ 208,787	$ 245,285	658,940	831,260
EXPENSES
Interest expense	38,756									209,321	261,244
Salaries and benefits	40,408									285,559	384,814
General and administrative	50,520									366,710	596,838
Depreciation and amortization	3,810									32,358	40,764
Total expenses	133,723	145,659	229,635	252,073	251,736	385,271	303,146	292,595	313,709	879,103	1,294,721
OTHER GAINS (LOSSES)
Reorganization items and fresh start accounting adjustments	464,563	(100)		(2,600)						(2,726)	(37,645)
Net losses on extinguishment of debt	(864)									(4,454)	(6,111)
Other net fair value gains	3,740									11,083	2,008
Other	0									8,515	7,219
Total other gains	467,439	484	(11,516)	10,463	12,987	(33,622)	2,824	(8,807)	72,810	12,418	33,205
Income (loss) before income taxes	520,989	(53,960)	(76,612)	(36,952)	(40,221)	(218,349)	(123,678)	(92,615)	4,386	(207,745)	(430,256)
Income tax benefit	(18)	189	(2,774)	(315)	249	(5,384)	455	1,694	(122)	(2,651)	(3,357)
Net income (loss)	521,007	$ (54,149)	$ (73,838)	$ (36,637)	$ (40,470)	$ (212,965)	$ (124,133)	$ (94,309)	$ 4,508	(205,094)	(426,899)
Comprehensive income (loss)	521,007									(205,002)	(426,889)
Parent Company [Member]
REVENUES
Interest income on loans	68									(48)	865
Other revenues, net	47									1,086	355
Total revenues	115									1,038	1,220
EXPENSES
Interest expense	7,519									111,696	134,660
Salaries and benefits	6,071									44,401	40,763
General and administrative	821									47,782	95,660
Depreciation and amortization	0									0	700
Corporate allocations	(11,779)									(76,537)	(86,309)
Other expenses, net	34									(615)	564
Total expenses	2,666									126,727	186,038
OTHER GAINS (LOSSES)
Reorganization items and fresh start accounting adjustments	458,511									(2,726)	(37,645)
Net losses on extinguishment of debt	(864)									(4,454)	(1,797)
Other net fair value gains	0									4,715	0
Other	0									(9,066)	0
Total other gains	457,647									(11,531)	(39,442)
Income (loss) before income taxes	455,096									(137,220)	(224,260)
Income tax benefit	(3,918)									(613)	(24,381)
Income (loss) before equity in income (losses) of consolidated subsidiaries and VIEs	459,014									(136,607)	(199,879)
Equity in income (losses) of consolidated subsidiaries and VIEs	61,993									(68,487)	(227,020)
Net income (loss)	521,007									(205,094)	(426,899)
Comprehensive income (loss)	$ 521,007									$ (205,002)	$ (426,889)