Goodwill and Other Intangible Assets (Schedule Of Components Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 73,530	$ 73,530
Accumulated Amortization	(46,386)	(41,828)
Total	27,144	31,702
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	52,430	52,430
Accumulated Amortization	(38,081)	(34,327)
Total	$ 14,349	$ 18,103
Useful Lives (in years)	11 years	11 years
Trade names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 15,400	$ 15,400
Accumulated Amortization	(4,973)	(4,491)
Total	$ 10,427	$ 10,909
Useful Lives (in years)	24 years	24 years
Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,300	$ 4,300
Accumulated Amortization	(3,332)	(3,010)
Total	$ 968	$ 1,290
Useful Lives (in years)	10 years	10 years