Derivatives and Hedging (Summary Of Cash Flow Interest Rate Contract Hedging Activity) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) Loss Recognized in Other Comprehensive Income (Loss) on Derivative	$ 0	$ (77)	$ (1,379)	$ 29
Interest Expense, net	(15,996)	(19,850)	(47,685)	(61,405)
Cash Flow Hedges [Member] \| Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of (Gain) Loss Recognized in Other Comprehensive Income (Loss) on Derivative	0	(77)	(1,379)	29
Reclassification out of Accumulated Other Comprehensive Income [Member] \| Cash Flow Hedges [Member] \| Interest Rate Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Income as a Result That a Forecasted Transaction is No Longer Probable of Occurring	0	0	3,390	0
Interest Expense, net	$ 224	$ 90	$ 688	$ (74)

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No definition available.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Interest and debt related expenses associated with nonoperating financing activities of the entity.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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