Business Combinations, Sale and Deconsolidation of Subsidiaries, and Noncontrolling Interest (Details 2)) (USD $)	12 Months Ended				1 Months Ended
	Dec. 31, 2012	Nov. 30, 2011 Foreign equity-method investee, purchaser of subsidiary interest	Feb. 28, 2011 European Acquisition Partnership, purchaser of subsidiary interest and portfolio assets	Feb. 28, 2011 Affiliate of Varde European Acquisition Partnership, purchaser of subsidiary interest and portfolio assets	Nov. 30, 2011 French Acquisition Partnerships	Nov. 30, 2011 French Acquisition Partnerships Foreign equity-method investee, purchaser of subsidiary interest item	Feb. 28, 2011 German Acquisition Partnerships	Nov. 30, 2012 Brazilian Acquisition Partnership
Subsidiary or Equity Method Investee [Line Items]
Consideration received on divestiture						$ 3,400,000	$ 22,500,000	$ 400,000
Beneficial ownership interest (as a percent)			13.00%	87.00%
Number of partnerships sold						16
Amount of cash, removed from balance sheet	2,855,000				800,000
Amount of Portfolio Assets, removed from balance sheet					500,000
Non-cash decrease in noncontrolling interest	9,334,000				600,000
Gain realized on transaction					2,800,000			400,000
Deferred gain on sale recognized					$ 1,000,000
Ownership interests in the foreign equity-method investee (as a percent)		36.80%
Sale of ownership interest (as a percent)								20.00%