Other Assets and Liabilities - Additional Information (Detail) $ in Thousands	6 Months Ended
	Jun. 30, 2015 USD ($) Location	Dec. 31, 2014 USD ($) Location
Other Assets and Other Liabilities [Line Items]
Real estate owned (REO)	$ 4,410	$ 4,391
Amount related to transfers into REO	5,000
REO liquidations	3,000
Negative market valuation adjustments on REO	$ 2,000
Sequoia
Other Assets and Other Liabilities [Line Items]
Number of REO properties recorded on balance sheet | Location	18	22