Restructuring Charges (Details) (USD $)	12 Months Ended			24 Months Ended	36 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2010	Dec. 31, 2011
Restructuring and Related Cost [Line Items]
Restructuring charges	$ 46,000,000	$ 81,000,000	$ 23,000,000
Cumulative amount paid since restructuring activities began	35,000,000	49,000,000			100,000,000
Restructuring reserve reversal				5,000,000
Severance Costs [Member]
Restructuring and Related Cost [Line Items]
Restructuring charges	12,000,000			87,000,000
Cumulative amount paid since restructuring activities began					81,000,000
Contract Termination and Other Associated Costs [Member]
Restructuring and Related Cost [Line Items]
Restructuring charges	34,000,000			22,000,000
Cumulative amount paid since restructuring activities began					$ 19,000,000