Risk Management and Use of Derivative Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Derivatives, Fair Value
Derivative assets, fair value, net	$ 11,148	$ 8,458
Derivative liability, fair value, net	(27,003)	(23,816)
Foreign currency forward | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	2,002	4,229
Foreign currency forward | Designated as hedging | Accounts payable, accrued expenses and other liabilities
Derivatives, Fair Value
Derivative liability, fair value, net	(11,928)	(2,533)
Foreign currency forward | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	1,521	0
Foreign currency collars | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	429	2,743
Interest rate swap | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	1,895	0
Interest rate swap | Designated as hedging | Accounts payable, accrued expenses and other liabilities
Derivatives, Fair Value
Derivative liability, fair value, net	(12,911)	(20,142)
Interest rate cap | Designated as hedging | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	0	1
Embedded derivatives | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	2,314	0
Embedded derivatives | Not designated | Accounts payable, accrued expenses and other liabilities
Derivatives, Fair Value
Derivative liability, fair value, net	(2,164)	(1,141)
Stock warrants | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	1,782	1,485
Swaption | Not designated | Other assets
Derivatives, Fair Value
Derivative assets, fair value, net	$ 1,205	$ 0