Consolidated Statements of Income (Unaudited) (Parenthetical) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Income [Abstract]
Interest income	$ 0	$ 0	$ 1	$ 1
Tax (benefit) expense on discontinued operations	0	0	0	0
Tax (benefit) expense on gain (loss) of dispositions from discontinued operations	$ 1	$ (34)	$ 2	$ (34)