Restructuring of Operations - Restructuring Charges and Related Payments and Adjustments (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Restructuring Reserve [Roll Forward]
Beginning balance	$ 25		$ 40
Charges to restructuring	10		23
Adjustments of accruals	(2)		(9)
Discontinued operations charges		1	1	3
Cash payments	(9)		(31)
Ending Balance	24		24
Employee Termination Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	14		27
Charges to restructuring	4		14
Adjustments of accruals	(1)		(8)
Discontinued operations charges
Cash payments	(5)		(21)
Ending Balance	12		12
Exit Costs
Restructuring Reserve [Roll Forward]
Beginning balance	11		13
Charges to restructuring	6		9
Adjustments of accruals	(1)		(1)
Discontinued operations charges			1
Cash payments	(4)		(10)
Ending Balance	$ 12		$ 12