Accrued Liabilities (Narrative) (Details) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Accrued Liabilities [Abstract]
Accrued product liability	$ 6,395,000	$ 6,052,000
Accrued payroll liability	5,721,000	6,472,000
Environmental accrued liability	1,875,000	2,250,000
Other accrued liabilities	$ 1,263,000	$ 1,261,000