Risk Management and Use of Derivative Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Derivatives, Fair Value
Asset Derivatives Fair Value at	$ 8,375	$ 3,780
Liability Derivatives Fair Value at	(14,581)	(21,812)
Interest rate caps \| Designated as Hedging Instrument \| Other Assets
Derivatives, Fair Value
Asset Derivatives Fair Value at	6	2
Stock warrants \| Not Designated as Hedging Instrument \| Other Assets
Derivatives, Fair Value
Asset Derivatives Fair Value at	3,753	2,160
Foreign currency contracts \| Designated as Hedging Instrument \| Other Assets
Derivatives, Fair Value
Asset Derivatives Fair Value at	3,629	0
Foreign currency contracts \| Designated as Hedging Instrument \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value
Liability Derivatives Fair Value at	(451)	(7,083)
Interest rate swap \| Designated as Hedging Instrument \| Other Assets
Derivatives, Fair Value
Asset Derivatives Fair Value at	987	1,618
Interest rate swap \| Designated as Hedging Instrument \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value
Liability Derivatives Fair Value at	(5,097)	(2,734)
Interest rate swap \| Not Designated as Hedging Instrument \| Accounts Payable and Accrued Liabilities
Derivatives, Fair Value
Liability Derivatives Fair Value at	$ (9,033)	$ (11,995)

Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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