Goodwill And Other Intangible Assets (Schedule Of Goodwill And Other Intangibles) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Goodwill And Other Intangible Assets [Line Items]
Goodwill, Impairment Loss	$ 46,792	$ 0	$ 0
Goodwill	81,404	128,208	$ 117,822
Finite-Lived Intangible Assets, Net	36,295
Identifiable intangible assets:
Total carrying value of identifiable intangibles	36,295	40,552
Intangible Assets, Net (Including Goodwill)	117,699	168,760
Customer relationships
Goodwill And Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	22,785	25,444
Identifiable intangible assets:
Finite-Lived Intangible Assets, Gross	29,568	29,647
Proprietary technology
Goodwill And Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	1,093	1,700
Identifiable intangible assets:
Finite-Lived Intangible Assets, Gross	6,185	6,203
Trade Names [Member]
Goodwill And Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Net	12,417	13,408
Noncompete agreements
Identifiable intangible assets:
Finite-Lived Intangible Assets, Gross	$ 1,854	$ 1,854
Minimum | Customer relationships
Identifiable intangible assets:
Identifiable Intangible Asset, Useful Life (Yrs)	10 years
Minimum | Trade Names [Member]
Identifiable intangible assets:
Identifiable Intangible Asset, Useful Life (Yrs)	2 years
Maximum | Customer relationships
Identifiable intangible assets:
Identifiable Intangible Asset, Useful Life (Yrs)	12 years
Maximum | Proprietary technology
Identifiable intangible assets:
Identifiable Intangible Asset, Useful Life (Yrs)	15 years
Maximum | Trade Names [Member]
Identifiable intangible assets:
Identifiable Intangible Asset, Useful Life (Yrs)	12 years