Goodwill And Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Historical Cost	$ 1,064,002	$ 881,419
Accumulated Amortization	(569,219)	(428,479)
Net	$ 494,783	$ 452,940
Trade names
Finite-Lived Intangible Asset, Useful Life	10 years 10 months 24 days	11 years 2 months 12 days
Weighted-Average Amortization Period, years	9 years 7 months 6 days
Historical Cost	$ 181,231	$ 147,997
Accumulated Amortization	(65,722)	(51,429)
Net	115,509	$ 96,568
Fair Value	$ 33,750		$ 5,866
Patent and patent licenses
Finite-Lived Intangible Asset, Useful Life	6 years 6 months	6 years 7 months 6 days
Historical Cost	$ 67,887	$ 67,724
Accumulated Amortization	(60,541)	(56,853)
Net	$ 7,346	$ 10,871
Customer relationships
Finite-Lived Intangible Asset, Useful Life	9 years 1 month 6 days	8 years 10 months 24 days
Weighted-Average Amortization Period, years	10 years 7 months 6 days
Historical Cost	$ 507,330	$ 447,070
Accumulated Amortization	(316,122)	(253,464)
Net	191,208	$ 193,606
Fair Value	$ 66,516		85,482
Other purchased intangibles
Finite-Lived Intangible Asset, Useful Life	4 years 4 months 24 days	4 years 9 months 18 days
Weighted-Average Amortization Period, years	3 years 3 months 18 days
Historical Cost	$ 307,554	$ 218,628
Accumulated Amortization	(126,834)	(66,733)
Net	180,720	151,895
Fair Value	$ 84,907	36,998	91,264
Trademarks
Weighted-Average Amortization Period, years	7 years 1 month 6 days
Fair Value	$ 3,285	$ 1,373	70,300
EVDY [Member] | Customer relationships
Fair Value			45,500
EVDY [Member] | Other purchased intangibles
Fair Value			88,267
EVDY [Member] | Trademarks
Fair Value			$ 70,300