CONSOLIDATED STATEMENTS OF INCOME (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Income Statement [Abstract]
Interest income	$ 0	$ 1	$ 1	$ 1
Tax (benefit) expense on gain (loss) of dispositions from discontinued operations	$ 0	$ (2)	$ (70)	$ (1)