Loans Receivable - Interest, Dividend and Discount Accretion Income (Detail) (USD $) In Thousands, unless otherwise specified	7 Months Ended	12 Months Ended
	Jul. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Receivables [Abstract]
Interest on loan assets	$ 5,770		$ 14,334	$ 11,736
Exit fee/prepayment penalty	1,787
Accretion of loan discount	2,086	2,086	4,121	8,333
Interest and dividends on REIT securities				1,054
Total interest, dividends and discount accretion	$ 9,643		$ 18,455	$ 21,123