Goodwill And Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 117,194
Historical Cost	1,180,474	$ 1,064,002
Accumulated Amortization	(650,567)	(569,219)
Net	529,907	494,783
Trade Names [Member]
Historical Cost	185,847	181,231
Accumulated Amortization	(73,789)	(65,722)
Net	$ 112,058	$ 115,509
Finite-Lived Intangible Asset, Useful Life	10 years 9 months 18 days	10 years 10 months 24 days
Patents And Patent Licenses [Member]
Historical Cost	$ 67,882	$ 67,887
Accumulated Amortization	(61,894)	(60,541)
Net	$ 5,988	$ 7,346
Finite-Lived Intangible Asset, Useful Life	6 years 6 months	6 years 6 months
Customer Relationships [Member]
Historical Cost	$ 583,620	$ 507,330
Accumulated Amortization	(350,206)	(316,122)
Net	$ 233,414	$ 191,208
Finite-Lived Intangible Asset, Useful Life	9 years 2 months 12 days	9 years 1 month 6 days
Other Purchased Intangibles [Member]
Historical Cost	$ 343,125	$ 307,554
Accumulated Amortization	(164,678)	(126,834)
Net	$ 178,447	$ 180,720
Finite-Lived Intangible Asset, Useful Life	4 years 6 months	4 years 4 months 24 days
2019 Business Acquisitions [Member] | Trade Names [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 3,548
Weighted-Average Amortization Period, years	6 years 8 months 12 days
2019 Business Acquisitions [Member] | Customer Relationships [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 76,934
Weighted-Average Amortization Period, years	11 years 7 months 6 days
2019 Business Acquisitions [Member] | Other Purchased Intangibles [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 15,452
Weighted-Average Amortization Period, years	2 years 1 month 6 days
2019 Business Acquisitions [Member] | Trademarks [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles	$ 21,260
Weighted-Average Amortization Period, years	2 years 10 months 24 days