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		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized Due to Ineffectiveness		$ 1		$ 45
Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (Effectiveness)	$ 928	5,552	$ 3,504	(10,973)
Gain/(Loss) Reclassified From OCI Into Income	$ 724	$ (1,391)	$ (810)	$ (4,273)