Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis Utilizing Significant Unobservable Inputs Reconciliation (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Assets
Fair Value, Beginning Balance	$ 12,060,487	$ 12,938,330	$ 12,245,112	$ 13,089,216
Total Gains (Losses) Included in Comprehensive Income (Loss)	(2,297)	(18,110)	9,492	(157,682)
Purchases and Other	1,708	82,404	45,288	156,061
Sales and Other	4,131	(28,235)	4,207	(28,235)
Originations/ Issuances	102,239	165,086	214,105	344,495
Settlements	(353,593)	(346,488)	(705,529)	(610,868)
Fair Value, Ending Balance	11,812,675	12,792,987	11,812,675	12,792,987
Liabilities
Fair Value, Beginning Balance	(10,788,987)	(11,368,081)	(11,027,667)	(11,347,792)
Total Gains (Losses) Included in Comprehensive Income (Loss)	(71,564)	(139,717)	(104,554)	(262,166)
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	(123,695)	(235,046)	(278,010)	(437,993)
Settlements	525,062	356,641	951,047	661,748
Fair Value, Ending Balance	(10,459,184)	(11,386,203)	(10,459,184)	(11,386,203)
Fair value of mortgage servicing rights sold	12,326	28,235	12,420	28,235
Loss on sale of mortgage servicing rights		(500)		(500)
Freestanding Derivative Instruments \| Interest Rate Lock Commitments
Assets
Fair Value, Beginning Balance		255
Liabilities
Fair Value, Beginning Balance	(714)		(4,193)	(1,070)
Total Gains (Losses) Included in Comprehensive Income (Loss)	(1,461)	92	2,018	907
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	0	0	0	0
Settlements	0	0	0	0
Fair Value, Ending Balance	(2,175)	(163)	(2,175)	(163)
Servicing Rights Related Liabilities
Assets
Fair Value, Beginning Balance		105,559
Liabilities
Fair Value, Beginning Balance				(117,000)
Total Gains (Losses) Included in Comprehensive Income (Loss)		1,903		5,197
Purchases and Other		0		0
Sales and Other		0		0
Originations/ Issuances		(27,886)		(27,886)
Settlements		10,717		18,864
Fair Value, Ending Balance		(120,825)		(120,825)
Mortgage-Backed Debt Related to Non-Residual Trusts
Assets
Fair Value, Beginning Balance		564,832
Liabilities
Fair Value, Beginning Balance	(498,768)		(514,025)	(582,340)
Total Gains (Losses) Included in Comprehensive Income (Loss)	(5,406)	(7,987)	(13,965)	(14,919)
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	0	0	0	0
Settlements	33,574	24,752	57,390	49,192
Fair Value, Ending Balance	(470,600)	(548,067)	(470,600)	(548,067)
HMBS Related Obligations
Assets
Fair Value, Beginning Balance		10,697,435
Liabilities
Fair Value, Beginning Balance	(10,289,505)		(10,509,449)	(10,647,382)
Total Gains (Losses) Included in Comprehensive Income (Loss)	(64,697)	(133,725)	(92,607)	(253,351)
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	(123,695)	(207,160)	(278,010)	(410,107)
Settlements	491,488	321,172	893,657	593,692
Fair Value, Ending Balance	(9,986,409)	(10,717,148)	(9,986,409)	(10,717,148)
Reverse Loans
Assets
Fair Value, Beginning Balance	10,599,732	10,872,891	10,742,922	10,763,816
Total Gains (Losses) Included in Comprehensive Income (Loss)	72,569	141,375	115,181	296,209
Purchases and Other	1,635	84,935	44,769	138,955
Sales and Other	0	0	0	0
Originations/ Issuances	84,972	118,807	172,034	245,958
Settlements	(318,239)	(307,771)	(634,237)	(534,701)
Fair Value, Ending Balance	10,440,669	10,910,237	10,440,669	10,910,237
Mortgage Loans Related to Non-Residual Trusts
Assets
Fair Value, Beginning Balance	440,219	506,337	450,377	526,016
Total Gains (Losses) Included in Comprehensive Income (Loss)	(3,343)	6,418	9,159	11,581
Purchases and Other	0	0	0	0
Sales and Other	(8,890)	0	(8,890)	0
Originations/ Issuances	0	0	0	0
Settlements	(21,980)	(24,576)	(44,640)	(49,418)
Fair Value, Ending Balance	406,006	488,179	406,006	488,179
Mortgage Loans Held For Sale
Assets
Fair Value, Beginning Balance	0		0
Total Gains (Losses) Included in Comprehensive Income (Loss)	6		6
Purchases and Other	0		0
Sales and Other	8,890		8,890
Originations/ Issuances	0		0
Settlements	(158)		(158)
Fair Value, Ending Balance	8,738		8,738
Charged-Off Loans
Assets
Fair Value, Beginning Balance	52,071	53,246	46,963	49,307
Total Gains (Losses) Included in Comprehensive Income (Loss)	8,161	9,668	22,752	24,044
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	0	0	0	0
Settlements	(10,606)	(11,852)	(20,089)	(22,289)
Fair Value, Ending Balance	49,626	51,062	49,626	51,062
Liabilities
Gains from instrument-specific credit risk	1,700	3,400	11,900	14,300
Receivables Related to Non-Residual Trusts
Assets
Fair Value, Beginning Balance	13,848	14,118	15,033	16,542
Total Gains (Losses) Included in Comprehensive Income (Loss)	533	618	3,102	151
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	0	0	0	0
Settlements	(2,540)	(2,055)	(6,294)	(4,012)
Fair Value, Ending Balance	11,841	12,681	11,841	12,681
Servicing Rights Carried at Fair Value
Assets
Fair Value, Beginning Balance	909,270	1,427,331	936,423	1,682,016
Total Gains (Losses) Included in Comprehensive Income (Loss)	(66,633)	(187,493)	(119,112)	(514,073)
Purchases and Other	73	(2,531)	519	17,106
Sales and Other	4,131	(28,235)	4,207	(28,235)
Originations/ Issuances	17,267	46,279	42,071	98,537
Settlements	0	0	0	0
Fair Value, Ending Balance	864,108	1,255,351	864,108	1,255,351
Freestanding Derivative Instruments \| Interest Rate Lock Commitments
Assets
Fair Value, Beginning Balance	45,347	64,407	53,394	51,519
Total Gains (Losses) Included in Comprehensive Income (Loss)	(13,590)	11,304	(21,596)	24,406
Purchases and Other	0	0	0	0
Sales and Other	0	0	0	0
Originations/ Issuances	0	0	0	0
Settlements	(70)	(234)	(111)	(448)
Fair Value, Ending Balance	$ 31,687	$ 75,477	$ 31,687	$ 75,477

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

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Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

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The gains (losses) included in earning that represent the difference between the sale price and the carrying value of mortgage servicing rights.

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No definition available.

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