Fair Values Of Assets And Liabilities Level 3 Rollforward (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		12 Months Ended
	Dec. 31, 2010	Sep. 30, 2010	Dec. 31, 2012	Dec. 31, 2011	Jun. 30, 2010	Jun. 30, 2009
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Interest Rate Swap Agreements - Assets			$ 133	$ 2,004
Interest Rate Swap Agreements - Liabilities			133	6,440
Investment in Money Market Fund						8,027
Included in Earnings - Investment in Money Market Fund					2,020
Settlements - Investment in Money Market Fund					(10,047)
Interest Rate Swap [Member] | Interest Rate Swap And Cap Agreements [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	15,654	17,829	6,493	39,317	97,831
Interest Rate Swap Agreements - Liabilities	(46,797)	(60,895)	(133)	(6,440)	(70,421)	(131,885)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(1,092)	(85)	(120)	1,090	394
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(464)	(8,218)	(66)	(50)	(36,761)
Interest Rate Swap [Member] | Other Assets [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(5,500)	(4,247)	(2,023)	(19,378)	(10,668)
Interest Rate Swap Agreements - Assets	23,058	27,364	133	2,004	26,194	24,267
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ 1,194	$ 5,417	$ 152	$ (1,676)	$ 12,595