Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis Utilizing Significant Unobservable Inputs Reconciliation (Detail) - USD ($) $ in Thousands	1 Months Ended	11 Months Ended	12 Months Ended
	Feb. 09, 2018	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	$ 10,883,766	$ 11,074,126	$ 12,245,112
Total Gains (Losses) Included in Comprehensive Loss	109,349	145,566	21,482
Purchases and Other	(7)	55	45,439
Sales and other	(100,399)	(797,018)	(81,815)
Originations/ Issuances	42,735	335,931	408,179
Settlements	(165,369)	(1,807,224)	(1,719,784)
Transfers out of Level 3		(14,565)	(34,847)
Fresh-Start Accounting Adjustment	304,051
Fair Value, Ending Balance	11,074,126	8,936,871	10,883,766
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	(9,524,079)	(9,650,229)	(11,027,667)
Total Gains (Losses) Included in Comprehensive Loss	(26,610)	(159,768)	(222,464)
Purchases and Other	0	0	0
Sales and other	0	356,621	0
Originations/ Issuances	(27,881)	(251,946)	(464,192)
Settlements	318,493	2,308,861	2,190,244
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	(390,152)
Fair Value, Ending Balance	(9,650,229)	(7,396,461)	(9,524,079)
Reverse Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	9,789,444	9,702,263	10,742,922
Total Gains (Losses) Included in Comprehensive Loss	31,476	202,844	242,288
Purchases and Other	0	0	44,769
Sales and other	0	(210,172)	0
Originations/ Issuances	33,300	224,001	337,378
Settlements	(151,957)	(1,716,161)	(1,577,913)
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	9,702,263	8,202,775	9,789,444
Mortgage Loans Related To Non-Residual Trusts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	301,435	299,790	450,377
Total Gains (Losses) Included in Comprehensive Loss	5,690	15,728	25,214
Purchases and Other	0	0	0
Sales and other	0	(159,344)	(88,842)
Originations/ Issuances	0	0	0
Settlements	(7,335)	(38,764)	(85,314)
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	299,790	117,410	301,435
Mortgage Loans Related To Residual Trusts and Other Loans Held for Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	0	304,051
Total Gains (Losses) Included in Comprehensive Loss	0	(830)
Purchases and Other	0	0
Sales and other	0	(287,068)
Originations/ Issuances	0	0
Settlements	0	(15,109)
Transfers out of Level 3		0
Fresh-Start Accounting Adjustment	304,051
Fair Value, Ending Balance	304,051	1,044	0
Mortgage Loans Held for Sale [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	68	67	0
Total Gains (Losses) Included in Comprehensive Loss	0	24	(131)
Purchases and Other	0	0	0
Sales and other	0	0	1,671
Originations/ Issuances	0	0	0
Settlements	(1)	(30)	(1,472)
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	67	61	68
Charged-off Loans [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	45,800	50,299	46,963
Total Gains (Losses) Included in Comprehensive Loss	8,843	32,411	39,072
Purchases and Other	0	0	0
Sales and other	0	0	0
Originations/ Issuances	0	0	0
Settlements	(4,344)	(34,270)	(40,235)
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	50,299	48,440	45,800
Receivables Related to Non-Residual Trusts [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	5,608	4,730	15,033
Total Gains (Losses) Included in Comprehensive Loss	848	48	5,224
Purchases and Other	0	0	0
Sales and other	0	0	0
Originations/ Issuances	0	0	0
Settlements	(1,726)	(2,833)	(14,649)
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	4,730	1,945	5,608
Servicing Rights Carried at Fair Value [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	714,774	688,466	936,423
Total Gains (Losses) Included in Comprehensive Loss	64,663	(96,873)	(263,629)
Purchases and Other	(7)	55	670
Sales and other	(100,399)	(140,434)	5,356
Originations/ Issuances	9,435	111,930	70,801
Settlements	0	0	0
Transfers out of Level 3		(14,565)	(34,847)
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	688,466	548,579	714,774
Freestanding Derivative Instruments [Member] | Interest Rate Lock Commitments [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	26,637	24,460	53,394
Total Gains (Losses) Included in Comprehensive Loss	(2,171)	(7,786)	(26,556)
Purchases and Other	0	0	0
Sales and other	0	0	0
Originations/ Issuances	0	0	0
Settlements	(6)	(57)	(201)
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	24,460	16,617	26,637
Freestanding Derivative Instruments [Member] | Interest Rate Lock Commitments [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	(269)	(3,023)	(4,193)
Total Gains (Losses) Included in Comprehensive Loss	(2,754)	2,696	3,924
Purchases and Other	0	0	0
Sales and other	0	0	0
Originations/ Issuances	0	0	0
Settlements	0	0	0
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	(3,023)	(327)	(269)
Mortgage-Backed Debt Related to Non-Residual Trusts [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	(348,682)	(344,002)	(514,025)
Total Gains (Losses) Included in Comprehensive Loss	(2,956)	(7,784)	(26,519)
Purchases and Other	0	0	0
Sales and other	0	0	0
Originations/ Issuances	0	0	0
Settlements	7,636	220,473	191,862
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	(344,002)	(131,313)	(348,682)
Mortgage Backed Debt Related To Residual Trusts [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	0	(390,152)
Total Gains (Losses) Included in Comprehensive Loss	0	1,331
Purchases and Other	0	0
Sales and other	0	356,621
Originations/ Issuances	0	0
Settlements	0	32,200
Transfers out of Level 3		0
Fresh-Start Accounting Adjustment	(390,152)
Fair Value, Ending Balance	(390,152)	0	0
HMBS Related Obligations [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Beginning Balance	(9,175,128)	(8,913,052)	(10,509,449)
Total Gains (Losses) Included in Comprehensive Loss	(20,900)	(156,011)	(199,869)
Purchases and Other	0	0	0
Sales and other	0	0	0
Originations/ Issuances	(27,881)	(251,946)	(464,192)
Settlements	310,857	2,056,188	1,998,382
Transfers out of Level 3		0	0
Fresh-Start Accounting Adjustment	0
Fair Value, Ending Balance	$ (8,913,052)	$ (7,264,821)	$ (9,175,128)