Goodwill And Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Historical Cost	$ 935,157	$ 881,419
Accumulated Amortization	(493,027)	(428,479)
Net	$ 442,130	$ 452,940
Trade Names [Member]
Weighted-Average Amortization Period, years	11 years 1 month 6 days	11 years 2 months 12 days
Historical Cost	$ 156,130	$ 147,997
Accumulated Amortization	(57,280)	(51,429)
Net	$ 98,850	$ 96,568
Patents And Patent Licenses [Member]
Weighted-Average Amortization Period, years	6 years 7 months 6 days	6 years 7 months 6 days
Historical Cost	$ 67,865	$ 67,724
Accumulated Amortization	(59,022)	(56,853)
Net	$ 8,843	$ 10,871
Customer Relationships [Member]
Weighted-Average Amortization Period, years	9 years 1 month 6 days	8 years 10 months 24 days
Historical Cost	$ 473,008	$ 447,070
Accumulated Amortization	(282,596)	(253,464)
Net	$ 190,412	$ 193,606
Other Purchased Intangibles [Member]
Weighted-Average Amortization Period, years	4 years 9 months 18 days	4 years 9 months 18 days
Historical Cost	$ 238,154	$ 218,628
Accumulated Amortization	(94,129)	(66,733)
Net	$ 144,025	$ 151,895