Restructuring and Asset Impairment Charges (Details) (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Restructuring And Asset Impairment Charges
Asset impairments	$ 1	$ 0	$ 1	$ 0
Total restructuring and asset impairment costs	9	10	14	36
Cost of revenue
Restructuring And Asset Impairment Charges
Restructuring costs	6	0	6	9
Operating Expenses [Member]
Restructuring And Asset Impairment Charges
Restructuring costs	$ 2	$ 10	$ 7	$ 27