Acquisitions, Goodwill And Other Intangible Assets (Schedule Of Other Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Acquired Intangible Assets
Finite-Lived Intangible Assets, Accumulated Amortization	$ 63,011		$ 66,627
Indefinite-Lived Intangible Assets - Purchased research and development	4,687		4,687
Intangible Assets, Gross (Excluding Goodwill)	172,358		167,562
Intangible Assets, Net (Excluding Goodwill)	109,347	$ 93,898	100,935
Customer Relationships
Acquired Intangible Assets
Finite-Lived Intangible Assets, Gross	99,890		94,560
Finite-Lived Intangible Assets, Accumulated Amortization	25,729		30,514
Finite-Lived Intangible Assets, Net	$ 74,161		$ 64,046
Customer Relationships | Minimum
Acquired Intangible Assets
Estimated useful life in years	6 years		6 years
Customer Relationships | Maximum
Acquired Intangible Assets
Estimated useful life in years	16 years		16 years
Patents
Acquired Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 53,890		$ 54,293
Finite-Lived Intangible Assets, Accumulated Amortization	29,257		28,255
Finite-Lived Intangible Assets, Net	$ 24,633		$ 26,038
Patents | Minimum
Acquired Intangible Assets
Estimated useful life in years	3 years		3 years
Patents | Maximum
Acquired Intangible Assets
Estimated useful life in years	19 years		19 years
Tradenames
Acquired Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 8,655		$ 8,935
Finite-Lived Intangible Assets, Accumulated Amortization	4,618		4,751
Finite-Lived Intangible Assets, Net	$ 4,037		$ 4,184
Tradenames | Minimum
Acquired Intangible Assets
Estimated useful life in years	3 years		3 years
Tradenames | Maximum
Acquired Intangible Assets
Estimated useful life in years	15 years		15 years
Non-compete Agreements
Acquired Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 4,568		$ 4,493
Finite-Lived Intangible Assets, Accumulated Amortization	3,020		2,800
Finite-Lived Intangible Assets, Net	$ 1,548		$ 1,693
Non-compete Agreements | Minimum
Acquired Intangible Assets
Estimated useful life in years	3 years		3 years
Non-compete Agreements | Maximum
Acquired Intangible Assets
Estimated useful life in years	6 years		6 years
Other
Acquired Intangible Assets
Finite-Lived Intangible Assets, Gross	$ 668		$ 594
Finite-Lived Intangible Assets, Accumulated Amortization	387		307
Finite-Lived Intangible Assets, Net	$ 281		$ 287
Other | Minimum
Acquired Intangible Assets
Estimated useful life in years	2 years	2 years
Other | Maximum
Acquired Intangible Assets
Estimated useful life in years	12 years	12 years