Consolidated Balance Sheets (Unaudited) (Parenthetical) (USD $)	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011
SHAREHOLDERS' EQUITY
Common stock, par value (in dollars per share)	$ 2.50	$ 2.50	$ 2.50
Common stock, shares authorized (in shares)	500,000,000	500,000,000	500,000,000
Common stock, shares issued (in shares)	94,436,177	83,483,796	83,481,737