Property, Plant and Equipment (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 1,261,952,000	$ 1,248,649,000
Accumulated Depreciation and Depletion	(944,283,000)	(930,515,000)
Property, Plant and Equipment, Net	317,669,000	318,134,000
Depreciation and depletion expense	48,700,000	55,900,000	61,200,000
Land [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	26,467,000	27,370,000
Quarries/mining properties [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	39,596,000	39,596,000
Buildings [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	145,082,000	147,115,000
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	937,559,000	911,753,000
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	27,805,000	31,060,000
Furniture and fixtures and other [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 85,443,000	$ 91,755,000