Securitized Debt Obligations, Net - Schedule of Information on Securitized Debt Obligations (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) Loans
Debt Instrument [Line Items]
Count | Loans	1
Principal Balance	$ 474,620
Book Value	$ 474,298
Term	2033-06
Loans [Member]
Debt Instrument [Line Items]
Count | Loans	1
Principal Balance	$ 644,788
Book Value	$ 641,262
Term	2023-06
LIBOR [Member]
Debt Instrument [Line Items]
Yield/Cost	1.94%
LIBOR [Member] | Loans [Member]
Debt Instrument [Line Items]
Yield/Cost	3.60%