Discontinued Operations (Summary Of Statements Of Operations As Discontinued Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income (loss) from discontinued operations, net of income taxes	$ (27,977)	$ 24,026	$ 20,866
Less: Net income attributable to noncontrolling interests	1,377	853	714
Net income (loss) attributable to Tile Coatings business	6,038	80,093	57,054
Discontinued Operations [Member] | Tile Coatings [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net sales	487,584	530,185	400,360
Cost of sales	385,890	413,987	310,858
Gross profit	101,694	116,198	89,502
Selling, general and administrative expenses	71,471	58,619	48,128
Restructuring and impairment charges	44,378	6,179	2,886
Interest expense	11,556	12,835	9,293
Interest earned	(122)	(125)	(119)
Foreign currency losses (gains), net	(2,397)	1,852	3,114
Miscellaneous expense (income), net	2,127	3,896	(1,003)
Income (loss) from discontinued operations before income taxes	(25,319)	32,942	27,203
Income tax expense	2,658	8,916	6,337
Income (loss) from discontinued operations, net of income taxes	(27,977)	24,026	20,866
Less: Net income attributable to noncontrolling interests	290	2	10
Net income (loss) attributable to Tile Coatings business	$ (28,267)	$ 24,024	$ 20,856