CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION (Parenthetical) (USD $) In Thousands, except Share data	Sep. 30, 2011	Dec. 31, 2010
Accounts receivable, allowance for doubtful accounts	$ 1,160	$ 1,630
Property, plant and equipment, accumulated depreciation	$ 226,665	$ 182,435
Capital Stock, par value	$ 1	$ 1
Capital Stock, authorized shares	50,000,000	50,000,000
Capital Stock, shares outstanding	16,168,392	15,841,341