Market Valuation Adjustments, Net (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Other market valuation adjustments
Other market valuation adjustments, net	$ (6,258)	$ (86)	$ (6,561)	$ (1,343)
Mortgage banking activities market valuation adjustments
Trading securities	36,336	(5,363)	38,265	(4,674)
MSRs	8,827	(527)	9,169	(544)
Derivative instruments, net	49,544	(3,282)	50,567	(6,398)
Total mortgage banking activities market valuation adjustments, net	52,957	(9,172)	91,121	(11,616)
Total Market Valuation Adjustments, Net	46,699	(9,258)	84,560	(12,959)
Residential Loans at Lower of Cost or Fair Value
Other market valuation adjustments
Other market valuation adjustments, net	38	405	78	498
Commercial Loans at Fair Value
Other market valuation adjustments
Other market valuation adjustments, net		111		122
Mortgage banking activities market valuation adjustments
Loans, at fair value	(345)		(345)
Trading Securities
Other market valuation adjustments
Other market valuation adjustments, net	(4,140)	16,349	(4,707)	49,824
Impairments on AFS Securities
Other market valuation adjustments
Other market valuation adjustments, net	(1,642)	(303)	(1,665)	(635)
REO
Other market valuation adjustments
Other market valuation adjustments, net	(558)	(162)	(331)	(144)
Other Derivative Instruments
Other market valuation adjustments
Other market valuation adjustments, net	44	(3,513)	64	(5,982)
Asset-backed Securities | Acacia
Other market valuation adjustments
Other market valuation adjustments, net		(12,973)		(45,026)
Residential Loans at Fair Value
Mortgage banking activities market valuation adjustments
Loans, at fair value	$ (41,405)		$ (6,535)