Risk Management and Use of Derivative Financial Instruments (Details 1) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Derivatives, Fair Value
Derivative assets, fair value, net	$ 43,945	$ 32,094
Derivative liability, fair value, net	(10,841)	(17,458)
Foreign currency forward contracts | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	41,850	24,051
Foreign currency forward contracts | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	0	5,120
Interest rate swap | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	0	71
Interest rate swap | Designated as hedging | Accounts payable, accrued expenses and other liabilities
Derivatives, Fair Value
Derivative liability, fair value, net	(10,732)	(14,554)
Foreign currency collars | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	4	0
Foreign currency collars | Designated as hedging | Accounts payable, accrued expenses and other liabilities
Derivatives, Fair Value
Derivative liability, fair value, net	(109)	0
Embedded derivatives | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	0	499
Stock warrants | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	1,782	1,848
Swaption | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	309	505
Swaption | Not designated | Accounts payable, accrued expenses and other liabilities
Derivatives, Fair Value
Derivative liability, fair value, net	$ 0	$ (2,904)