Real Estate And Lending Activities (List Of Assets Purchased As Part Of Acquisitions) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2011	Mar. 31, 2012
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total	$ 194,579	$ 396,500
Land [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total	16,151
Building [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total	157,834
Net Investment In Direct Financing Leases [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total		200,000
Mortgage Loans [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total		100,000
Other Loans [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total	5,233	93,200
Equity Investments [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total	1,268	3,300
Intangible Lease Assets [Member]
Real Estate Assets Purchased As Part Of Acquisitions [Line Items]
Total	$ 14,093
Weighted average useful life of acquired intangible lease assets (in years)	23.1