Summary Of Significant Accounting Policies (Schedule Of Accumulated Other Comprehensive Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013		Sep. 30, 2012
Increase (Decrease) In Accumulated Other Comprehensive Loss [Roll Forward]
Balance, December 31, 2012			$ 24,743
Change excluding amounts reclassified from accumulated other comprehensive income			(6,804)
Amounts reclassified from accumulated other comprehensive income			(2,792)
Net other comprehensive income	(517)	(615)	(9,596)		(1,804)
Balance, September 30, 2013	15,147		15,147
Loss On Investments [Member]
Increase (Decrease) In Accumulated Other Comprehensive Loss [Roll Forward]
Balance, December 31, 2012			0
Change excluding amounts reclassified from accumulated other comprehensive income			34
Amounts reclassified from accumulated other comprehensive income			0
Net other comprehensive income			34
Balance, September 30, 2013	34		34
(Gain) Loss On Cash Flow Hedges [Member]
Increase (Decrease) In Accumulated Other Comprehensive Loss [Roll Forward]
Balance, December 31, 2012			7,489
Change excluding amounts reclassified from accumulated other comprehensive income			(6,735)
Amounts reclassified from accumulated other comprehensive income			(1,802)	[1]
Net other comprehensive income			(8,537)
Balance, September 30, 2013	(1,048)		(1,048)
Defined Benefit Pension Plan [Member]
Increase (Decrease) In Accumulated Other Comprehensive Loss [Roll Forward]
Balance, December 31, 2012			17,254
Change excluding amounts reclassified from accumulated other comprehensive income			(103)
Amounts reclassified from accumulated other comprehensive income			(990)	[2]
Net other comprehensive income			(1,093)
Balance, September 30, 2013	$ 16,161		$ 16,161

[1] This reclassification component is included in interest expense (see Note 7 for additional information).

[2] This reclassification component is included in the computation of net periodic benefit cost (see Note 14 for additional information).