Loan Participations Payable, net (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Loan Participations Payable, net [Line Items]
Loan participations payable, net	$ 205,781	$ 152,086
Unamortized discounts and deferred financing costs, net	(30,796)	(31,566)
Unfunded commitments	540,865
Loans receivable, net	$ 1,569,634	$ 1,539,696
Total loan participations payable, net
Loan Participations Payable, net [Line Items]
Weighted average interest rate	4.60%	4.30%
Total loan participations payable, net
Loan Participations Payable, net [Line Items]
Loan Participations Payable, gross	$ 206,875	$ 153,000
Unamortized discounts and deferred financing costs, net	(1,094)	(914)
Total loan participations payable, net
Loan Participations Payable, net [Line Items]
Loans receivable, net	205,600	$ 153,000
Loan Participation Payable Three
Loan Participations Payable, net [Line Items]
Unfunded commitments	$ 32,600