Restructuring of Operations - Additional Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 employee	Mar. 31, 2012	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2	$ 5
Estimated reduction of employees over the next two years (in employees)	600
Restructuring and related activities, completion date period	2 years
Restructuring accruals	33		40
Fiscal Year 2013
Restructuring Cost and Reserve [Line Items]
Restructuring accruals	20
Thereafter
Restructuring Cost and Reserve [Line Items]
Restructuring accruals	13
Total Restructuring Costs including Cost Associated with Discontinued Operations
Restructuring Cost and Reserve [Line Items]
Restructuring charges	3	6
Discontinued Operations
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1	1
Employee Termination Benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		4
Restructuring accruals	21		27
Exit Costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		2
Restructuring accruals	$ 12		$ 13