Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2013	Dec. 31, 2012
Condensed Consolidated Balance Sheets
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	32,747,665	32,727,731
Common stock, shares outstanding (in shares)	21,282,558	21,262,624
Treasury stock, shares (in shares)	11,465,107	11,465,107