Unaudited Condensed Consolidated Balance Sheet (Parenthetical) (USD $)	Jun. 30, 2012	Dec. 31, 2011
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	225,785,767	224,665,395
Common stock, shares outstanding	214,771,352	222,955,853