Reporting for Segments (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Depreciation and amortization expense by segment
Total segment depreciation and amortization	$ 48,647	$ 50,820	$ 52,680
Unallocated depreciation and amortization	14,846	26,116	35,458
Total depreciation and amortization	63,493	76,936	88,138
Electronic Materials [Member]
Depreciation and amortization expense by segment
Total segment depreciation and amortization	10,092	11,586	13,382
Performance Coatings [Member]
Depreciation and amortization expense by segment
Total segment depreciation and amortization	17,415	17,004	17,726
Color and Glass Performance Materials [Member]
Depreciation and amortization expense by segment
Total segment depreciation and amortization	6,088	7,012	6,520
Polymer Additives [Member]
Depreciation and amortization expense by segment
Total segment depreciation and amortization	10,999	10,776	10,492
Specialty Plastics [Member]
Depreciation and amortization expense by segment
Total segment depreciation and amortization	2,014	2,369	2,610
Pharmaceuticals [Member]
Depreciation and amortization expense by segment
Total segment depreciation and amortization	$ 2,039	$ 2,073	$ 1,950