Segment Reporting - Select Financial Information of Reportable Segments (Detail) - 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
Segment Reporting Information [Line Items]
Net servicing revenue and fees	$ 128,685									$ 339,334	$ 346,682
Net gains on sales of loans	27,963									161,710	284,391
Net fair value gains on reverse loans and related HMBS obligations	10,576									46,833	42,419
Interest income on loans	3,387									1,832	41,195
Other revenues	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
Interest expense	38,756									209,321	261,244
Depreciation and amortization	3,810									32,358	40,764
Goodwill and intangible assets impairment	0	10,000	12,700		1,000					23,660	0
Other expenses, net	91,157									613,764	992,713
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
Reorganization items and fresh start accounting adjustments	464,563	(100)		(2,600)						(2,726)	(37,645)
Other gains (losses)	2,876									15,144	70,850
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)
Total assets			11,284,526			14,164,197				11,284,526	14,164,197
Late fees waived as an incentive for borrowers refinancing loans	5,100									45,400	56,800
Operating Segments [Member] | Servicing [Member]
Segment Reporting Information [Line Items]
Net servicing revenue and fees	127,503									321,833	328,736
Net gains on sales of loans	216									564	607
Net fair value gains on reverse loans and related HMBS obligations	0									0	0
Interest income on loans	3,381									1,792	41,147
Other revenues	14,451									86,481	94,558
Total revenues	145,551									410,670	465,048
Interest expense	9,606									15,356	53,593
Depreciation and amortization	3,252									14,062	34,242
Goodwill and intangible assets impairment										7,400
Other expenses, net	48,649									296,439	563,087
Total expenses	61,507									333,257	650,922
Reorganization items and fresh start accounting adjustments	(14,588)									0	0
Other gains (losses)	158									(6,878)	63,548
Income (loss) before income taxes	69,614									70,535	(122,326)
Total assets			1,900,630			2,957,173				1,900,630	2,957,173
Operating Segments [Member] | Originations [Member]
Segment Reporting Information [Line Items]
Net servicing revenue and fees	0									0	0
Net gains on sales of loans	27,490									159,787	280,967
Net fair value gains on reverse loans and related HMBS obligations	0									0	0
Interest income on loans	6									40	48
Other revenues	2,389									23,734	31,329
Total revenues	29,885									183,561	312,344
Interest expense	9,675									29,445	41,555
Depreciation and amortization	265									15,691	2,811
Goodwill and intangible assets impairment										16,260
Other expenses, net	21,580									156,534	199,994
Total expenses	31,520									217,930	244,360
Reorganization items and fresh start accounting adjustments	9,612									0	0
Other gains (losses)	0									0	(719)
Income (loss) before income taxes	7,977									(34,369)	67,265
Total assets			1,017,847			877,193				1,017,847	877,193
Operating Segments [Member] | Reverse Mortgage [Member]
Segment Reporting Information [Line Items]
Net servicing revenue and fees	2,029									22,361	27,566
Net gains on sales of loans	0									0	0
Net fair value gains on reverse loans and related HMBS obligations	10,576									46,833	42,419
Interest income on loans	0									0	0
Other revenues	602									5,581	2,750
Total revenues	13,207									74,775	72,735
Interest expense	11,956									52,824	31,435
Depreciation and amortization	228									1,632	3,010
Goodwill and intangible assets impairment										0
Other expenses, net	9,579									64,832	99,185
Total expenses	21,763									119,288	133,630
Reorganization items and fresh start accounting adjustments	7,423									0	0
Other gains (losses)	0									0	(1,345)
Income (loss) before income taxes	(1,133)									(44,513)	(62,240)
Total assets			8,460,374			10,100,149				8,460,374	10,100,149
Operating Segments [Member] | Corporate and Other [Member]
Segment Reporting Information [Line Items]
Net servicing revenue and fees	0									55	0
Net gains on sales of loans	0									0	0
Net fair value gains on reverse loans and related HMBS obligations	0									0	0
Interest income on loans	0									0	0
Other revenues	89									1,498	933
Total revenues	89									1,553	933
Interest expense	7,519									111,696	134,661
Depreciation and amortization	65									973	701
Goodwill and intangible assets impairment										0
Other expenses, net	12,808									107,578	150,247
Total expenses	20,392									220,247	285,609
Reorganization items and fresh start accounting adjustments	462,116									(2,726)	(37,645)
Other gains (losses)	2,718									22,022	9,366
Income (loss) before income taxes	444,531									(199,398)	(312,955)
Total assets			212,761			460,193				212,761	460,193
Eliminations [Member]
Segment Reporting Information [Line Items]
Net servicing revenue and fees	(847)									(4,915)	(9,620)
Net gains on sales of loans	257									1,359	2,817
Net fair value gains on reverse loans and related HMBS obligations	0									0	0
Interest income on loans	0									0	0
Other revenues	(869)									(8,063)	(12,997)
Total revenues	(1,459)									(11,619)	(19,800)
Interest expense	0									0	0
Depreciation and amortization	0									0	0
Goodwill and intangible assets impairment										0
Other expenses, net	(1,459)									(11,619)	(19,800)
Total expenses	(1,459)									(11,619)	(19,800)
Reorganization items and fresh start accounting adjustments	0									0	0
Other gains (losses)	0									0	0
Income (loss) before income taxes	0									0	0
Total assets			$ (307,086)			$ (230,511)				(307,086)	(230,511)
Intercompany [Member] | Operating Segments [Member] | Servicing [Member]
Segment Reporting Information [Line Items]
Net servicing revenue and fees	800									4,900	9,600
Other revenues	900									8,000	12,900
Late fees waived as an incentive for borrowers refinancing loans	$ 300									$ 1,400	$ 2,800