Derivatives (Activity In Accumulated Other Comprehensive Income (Loss) Related To Interest Rate Swaps) (Details) (USD $) In Thousands, unless otherwise specified			9 Months Ended				3 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Interest Rate Swap	Sep. 30, 2012 Interest Rate Swap	Dec. 31, 2012 Interest Rate Swap	Dec. 31, 2011 Interest Rate Swap	Sep. 30, 2013 Interest Rate Swap
Derivatives, Fair Value [Line Items]
Accumulated Other Comprehensive Income (Loss), before Tax	$ (156,536)	$ (134,923)	$ (7,909)	$ (11,170)	$ (10,398)	$ (10,714)
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred							1,927
Accumulated Other Comprehensive Income (Loss) from Interest Rate Swaps [Roll Forward]
Other comprehensive income (loss) recognized during the period			$ 2,489	$ (456)