Residential Loans at Fair Value - Reconciliation of the Changes in Residential Loans Held for Sale to the Amounts Presented in the Consolidated Statements of Cash Flows (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Receivables [Abstract]
Loans Receivable Held-for-sale, Amount	$ 630,456	$ 278,474	$ 1,015,607	$ 45,065
Purchases and originations of residential loans held for sale	4,453,761	4,848,332	8,037,309	5,281,349
Proceeds from sales of and payments on residential loans held for sale	(4,045,058)	(3,522,518)	(8,104,759)	(3,749,979)
Realized gains on sales of loans	102,517	67,218	189,350	75,526
Change in Unrealized Gain Loss on Loans Held for Sale	23,353	(15,897)	19,177	(2,271)
Interest and Fee Income, Loans Held-for-sale, Mortgages	8,721	8,473	17,066	9,261
Transfers from residential loans held for investment	0	43	0	5,183
Other	(162)	90	(162)	81
Loans Receivable Held-for-sale, Amount	$ 1,173,588	$ 1,664,215	$ 1,173,588	$ 1,664,215