Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2011	Dec. 31, 2010
Consolidated Balance Sheets [Abstract]
Common stock, par value	$ 0.625	$ 0.625
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	63,065,931	62,750,994
Repurchased common stock, shares	7,468,869	7,884,597