Cash Flows Related to Unconsolidated Variable Interest Entity's Sponsored by Redwood (Detail) (Variable Interest Entity, Not Primary Beneficiary, USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Cash proceeds	$ 1,705,504	$ 277,269	$ 3,859,354	$ 972,073
MSR fees received	2,099	137	3,075	154
Funding of compensating interest	(145)	(13)	(263)	(16)
Cash flows received on retained securities	$ 9,883	$ 2,071	$ 14,950	$ 3,099