Real Estate (Summary Of Real Estate Subject To Operating Leases) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Property Subject to or Available for Operating Lease [Line Items]
Real estate subject to operating leases, gross	$ 4,544,034	$ 4,038,690
Less accumulated depreciation and amortization	(393,339)	(331,781)
Real estate subject to operating leases before work in process	4,150,695	3,706,909
Accounted for using the operating method, net of accumulated depreciation and amortization	4,221,892	3,793,416
Land And Improvements [Member]
Property Subject to or Available for Operating Lease [Line Items]
Real estate subject to operating leases, gross	1,637,830	1,473,671
Buildings And Improvements [Member]
Property Subject to or Available for Operating Lease [Line Items]
Buildings and improvements	2,904,914	2,563,729
Leasehold Interests [Member]
Property Subject to or Available for Operating Lease [Line Items]
Leasehold interests	1,290	1,290
Work In Progress [Member]
Property Subject to or Available for Operating Lease [Line Items]
Work in progress	$ 71,197	$ 86,507