Goodwill And Other Intangible Assets (Details Of Amortizable Intangible Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Amortization Of Intangible Assets [Line Items]
Total gross amortizable intangible assets	$ 190,642	$ 187,728
Total accumulated amortization	(82,927)	(72,595)
Amortizable intangible assets, net	107,715	115,133
Patents [Member]
Amortization Of Intangible Assets [Line Items]
Total gross amortizable intangible assets	5,504	5,434
Total accumulated amortization	(5,482)	(5,413)
Land Rights [Member]
Amortization Of Intangible Assets [Line Items]
Total gross amortizable intangible assets	3,053	2,900
Total accumulated amortization	(1,549)	(1,378)
Technology/Know-how And Other [Member]
Amortization Of Intangible Assets [Line Items]
Total gross amortizable intangible assets	115,270	112,940
Total accumulated amortization	(58,973)	(50,973)
Customer Relationships [Member]
Amortization Of Intangible Assets [Line Items]
Total gross amortizable intangible assets	66,815	66,454
Total accumulated amortization	$ (16,923)	$ (14,831)