Revenue (Revenues Disaggregated By Geography And Reportable Segment) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total net sales	$ 1,018,366	$ 1,082,223	$ 996,382
Performance Colors And Glass [Member]
Disaggregation of Revenue [Line Items]
Total net sales	648,692	691,196	638,322
Color Solutions [Member]
Disaggregation of Revenue [Line Items]
Total net sales	369,674	391,027	358,060
EMEA [Member]
Disaggregation of Revenue [Line Items]
Total net sales	435,131	470,401	419,101
EMEA [Member] | Performance Colors And Glass [Member]
Disaggregation of Revenue [Line Items]
Total net sales	298,197	328,299	284,979
EMEA [Member] | Color Solutions [Member]
Disaggregation of Revenue [Line Items]
Total net sales	136,934	142,102	134,122
United States [Member]
Disaggregation of Revenue [Line Items]
Total net sales	359,267	379,913	356,483
United States [Member] | Performance Colors And Glass [Member]
Disaggregation of Revenue [Line Items]
Total net sales	197,494	207,012	201,753
United States [Member] | Color Solutions [Member]
Disaggregation of Revenue [Line Items]
Total net sales	161,773	172,901	154,730
Asia Pacific [Member]
Disaggregation of Revenue [Line Items]
Total net sales	139,916	145,291	132,025
Asia Pacific [Member] | Performance Colors And Glass [Member]
Disaggregation of Revenue [Line Items]
Total net sales	102,431	103,649	95,682
Asia Pacific [Member] | Color Solutions [Member]
Disaggregation of Revenue [Line Items]
Total net sales	37,485	41,642	36,343
Latin America [Member]
Disaggregation of Revenue [Line Items]
Total net sales	84,052	86,618	88,773
Latin America [Member] | Performance Colors And Glass [Member]
Disaggregation of Revenue [Line Items]
Total net sales	50,570	52,236	55,908
Latin America [Member] | Color Solutions [Member]
Disaggregation of Revenue [Line Items]
Total net sales	$ 33,482	$ 34,382	$ 32,865