CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Interest income	$ 2	$ 3	$ 2
Tax (benefit) expense on discontinued operations	0	0	0
Tax (benefit) expense on gain (loss) of dispositions from discontinued operations	$ 87	$ (5)	$ (166)