Consolidated Statements of Equity (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash dividends on common stock, per share	$ 0.04	$ 0.76	$ 1.00
Common stock, par value	$ 1	$ 1	$ 1
Common stock, shares authorized	460	460	460