Summary of Other Assets (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Line Items]
Margin receivable	$ 72,110	$ 71,976
Investment receivable	5,461	1,741
REO	3,550	5,669
Income tax receivables	4,712	4,741
MSRs	2,064
Prepaid expenses	989	1,706
Fixed assets and leasehold improvements	559	2,048
Other	663	381
Total Other Assets	$ 90,108	$ 88,262