Carrying Values and Estimated Fair Values of Assets and Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Assets
Derivative assets	$ 2,963		$ 2,373
Mortgage servicing rights	2,064
Carrying Value
Assets
Residential loans, held-for-sale	256,077		395,237
Commercial loans, at fair value	12,176		12,129
Trading securities	294,799		253,142
Available-for-sale securities	1,016,929		728,695
Cash and cash equivalents	69,519		267,176
Restricted cash	18,512		14,987
Accrued interest receivable	15,850		15,840
Derivative assets	2,963		2,373
Mortgage servicing rights	2,064	[1]
REO	3,550	[1]	5,669	[1]
Margin receivable	72,110	[1]	71,976	[1]
Liabilities
Short-term debt	455,419		428,056
Accrued interest payable	6,800		8,134
Derivative liabilities	114,473		127,564
ABS issued	3,563,873		4,139,355
Long-term debt	139,500		139,500
Carrying Value | Residential Loans Held For Investment
Assets
Loans, held-for-investment	3,215,737		3,799,648
Carrying Value | Commercial Loans Held For Investment
Assets
Loans, held-for-investment	246,783		157,726
Fair Value
Assets
Residential loans, held-for-sale	259,659		401,909
Commercial loans, at fair value	12,176		12,129
Trading securities	294,799		253,142
Available-for-sale securities	1,016,929		728,695
Cash and cash equivalents	69,519		267,176
Restricted cash	18,512		14,987
Accrued interest receivable	15,850		15,840
Derivative assets	2,963		2,373
Mortgage servicing rights	2,064	[1]
REO	4,335	[1]	5,669	[1]
Margin receivable	72,110	[1]	71,976	[1]
Liabilities
Short-term debt	455,419		428,056
Accrued interest payable	6,800		8,134
Derivative liabilities	114,473		127,564
ABS issued	3,117,075		3,467,054
Long-term debt	72,540		57,195
Fair Value | Residential Loans Held For Investment
Assets
Loans, held-for-investment	2,830,600		3,306,441
Fair Value | Commercial Loans Held For Investment
Assets
Loans, held-for-investment	$ 248,667		$ 158,780

[1] These assets are included in Other Assets on our consolidated balance sheets.