Equity Investment in Real Estate and the Managed REITs (Details 2) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Investmens in REITs
Equity method investments	$ 564,092	$ 565,626
Managed REITs
Investmens in REITs
Equity method investments	353,027	353,145
Managed REITs | CPA: 16 - Global
Investmens in REITs
Equity method investment, ownership percentage	18.456%	18.33%
Equity method investments	294,339	296,301
Managed REITs | CPA:16 - Global operating partnership
Investmens in REITs
Equity method investment, ownership percentage	0.015%	0.015%
Equity method investments	14,220	17,140
Managed REITs | CPA: 17 - Global
Investmens in REITs
Equity method investment, ownership percentage	1.429%	1.29%
Equity method investments	43,368	38,977
Managed REITs | CPA:17 - Global operating partnership
Investmens in REITs
Equity method investment, ownership percentage	0.015%	0.015%
Managed REITs | CWI
Investmens in REITs
Equity method investment, ownership percentage	0.447%	0.40%
Equity method investments	1,147	774
Managed REITs | CWI operating partnership
Investmens in REITs
Equity method investment, ownership percentage	0.015%	0.015%
Equity method investments	$ (47)	$ (47)