Derivative Instruments And Hedging Activities (Schedule Of Derivative Instruments In Consolidated Statements Of Operations) (Details) - Cash Flow Interest Rate Contracts [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized Due to Ineffectiveness		$ 33		$ 46
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (Effectiveness)	$ 3,340	(7,099)	$ 2,576	(16,525)
Loss Reclassified From OCI Into Income	$ 622	$ 1,537	$ 1,534	$ 2,882