Goodwill And Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Historical Cost	$ 1,274,073	$ 1,275,048
Accumulated Amortization	(813,300)	(750,180)
Net	460,773	524,868
Trade Names [Member]
Historical Cost	194,131	193,202
Accumulated Amortization	(90,848)	(82,552)
Net	$ 103,283	$ 110,650
Finite-Lived Intangible Asset, Useful Life	10 years	10 years 2 months 12 days
Patents And Patent Licenses [Member]
Historical Cost	$ 67,925	$ 67,921
Accumulated Amortization	(64,324)	(63,143)
Net	$ 3,601	$ 4,778
Finite-Lived Intangible Asset, Useful Life	6 years 6 months	6 years 6 months
Customer Relationships [Member]
Historical Cost	$ 634,319	$ 630,730
Accumulated Amortization	(425,977)	(392,228)
Net	$ 208,342	$ 238,502
Finite-Lived Intangible Asset, Useful Life	8 years 4 months 24 days	8 years 6 months
Other Purchased Intangibles [Member]
Historical Cost	$ 377,698	$ 383,195
Accumulated Amortization	(232,151)	(212,257)
Net	$ 145,547	$ 170,938
Finite-Lived Intangible Asset, Useful Life	4 years 4 months 24 days	4 years 3 months 18 days