Debt (Grouping Of Debt Between Fixed And Variable As Well As Secured And Unsecured) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Schedule of Long-term Debt, By Type [Line Items]
Total	$ 2,096,067	[1]	$ 2,299,844	[1]
As To Interest Rate [Member]
Schedule of Long-term Debt, By Type [Line Items]
Fixed-rate debt	1,823,554		2,136,265
Variable-rate debt	272,513		163,579
Total	2,096,067		2,299,844
As To Collateralization [Member]
Schedule of Long-term Debt, By Type [Line Items]
Unsecured debt	1,416,500		1,572,057
Secured debt	679,567		727,787
Total	$ 2,096,067		$ 2,299,844

[1] Consolidated variable interest entities' assets held as collateral and debt included in the above balances (see Note 16):