Summary of Activity in Allowance for Losses on Residential Loans (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for (reversal of) provision for loan losses	$ 4,737	$ 3,648	$ 16,151
Residential Loans
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	28,504	66,881	62,432
Charge-offs, net	(4,525)	(11,903)	(11,095)
Provision for (reversal of) provision for loan losses	1,448	171	15,544
Deconsolidation adjustment		(26,645)
Balance at End of Period	$ 25,427	$ 28,504	$ 66,881