Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Statement of Financial Position [Abstract]
Accounts receivable, less allowance for doubtful accounts	$ 100	$ 101
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	25,000,000	25,000,000
Preferred Stock, Shares Outstanding	0	0
Common stock, par value	$ 0.1	$ 0.1
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	313,938,978	319,615,965
Common stock, shares outstanding	313,938,978	319,615,965