Debt (Grouping Of Debt Between Fixed And Variable As Well As Secured And Unsecured) (Details) - USD ($) $ in Thousands		Jun. 30, 2017	Dec. 31, 2016
Schedule of Long-term Debt, By Type [Line Items]
Total	[1]	$ 2,291,474	$ 2,356,528
As To Interest Rate [Member]
Schedule of Long-term Debt, By Type [Line Items]
Fixed-rate debt		2,069,295	2,089,769
Variable-rate debt		222,179	266,759
Total		2,291,474	2,356,528
As To Collateralization [Member]
Schedule of Long-term Debt, By Type [Line Items]
Unsecured debt		1,869,984	1,913,399
Secured debt		421,490	443,129
Total		$ 2,291,474	$ 2,356,528

[1] Consolidated variable interest entities' assets held as collateral and debt included in the above balances at March 31, 2017 and December 31, 2016 are Property, net of $216,223 and $476,117; Accrued Rent and Accounts Receivable, net of $9,723 and $11,066; Cash and Cash Equivalents of $7,797 and $9,560; Debt, net of $46,902 and $47,112.