Summary Of Significant Accounting Policies (Composition Of Intangible And Other Long-term Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Intangible Assets by Major Class [Line Items]
Finite-Lived Intangible Assets, Net, Total	$ 213,205	$ 304,061
Acquired Finite-lived Intangible Asset, Amount	296,725	385,447
Finite-Lived Intangible Assets, Accumulated Amortization	(83,520)	(81,386)
Customer Relationships [Member]
Schedule of Intangible Assets by Major Class [Line Items]
Finite-Lived Intangible Assets, Net, Total	192,155	274,741
Acquired Finite-lived Intangible Asset, Amount	257,364	339,695
Finite-Lived Intangible Assets, Accumulated Amortization	(65,209)	(64,954)
Trade Names [Member]
Schedule of Intangible Assets by Major Class [Line Items]
Finite-Lived Intangible Assets, Net, Total	20,748	28,114
Acquired Finite-lived Intangible Asset, Amount	36,119	41,265
Finite-Lived Intangible Assets, Accumulated Amortization	(15,371)	(13,151)
Noncompete Agreements [Member]
Schedule of Intangible Assets by Major Class [Line Items]
Finite-Lived Intangible Assets, Net, Total	302	1,206
Acquired Finite-lived Intangible Asset, Amount	3,242	4,487
Finite-Lived Intangible Assets, Accumulated Amortization	$ (2,940)	$ (3,281)