CONDENSED CONSOLIDATED STATEMENTS OF FINANCIAL POSITION (Parenthetical) (USD $)
In Thousands, except Share data, unless otherwise specified
Mar. 31, 2015
Dec. 31, 2014
Statement of Financial Position [Abstract]    
Accounts receivable, allowance for doubtful accounts $ 906 $ 476
Property, plant and equipment, accumulated depreciation $ 221,200 $ 225,092
Capital Stock, par value (in dollars per share) $ 1 $ 1
Capital Stock, authorized shares (shares) 50,000,000 50,000,000
Capital Stock, shares outstanding (shares) 18,605,116 18,403,109