Assets and Liabilities Measured at Fair Value on Non-Recurring Basis (Detail) (Fair Value, Measurements, Nonrecurring, USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Residential loans, at lower of cost or fair value	$ 1,122	$ 1,122
REO	2,117	2,117
Residential Loans at Lower of Cost or Fair Value
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Gain (Loss) on assets measured at fair value on a non-recurring basis	37	42
REO
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Gain (Loss) on assets measured at fair value on a non-recurring basis	(368)	(459)
Level 3
Fair Value, Assets and Liabilities Measured on Nonrecurring Basis [Line Items]
Residential loans, at lower of cost or fair value	1,122	1,122
REO	$ 2,117	$ 2,117