Consolidated Condensed Balance Sheets (unaudited) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Shareholders' equity
Allowance for doubtful accounts (in dollars, thousands)	$ 1,171	$ 1,565
Common Stock, par value (in dollars per share)	$ 1.50	$ 1.50
Common Stock, shares authorized (in shares)	75,000	75,000
Common Stock, shares issued (in shares)	18,572	18,572
Treasury Stock, shares (in shares)	962	1,026