Restructuring and Other Costs (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period			$ 31
Accruals	(2)	37	17	65	65
Payments			(39)		(49)
Balance, end of period	9	16	9	16	31
Severance Benefits and Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period			31
Accruals			2		47
Payments			(29)		(38)
Balance, end of period	4	9	4	9	31
Professional Fees [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period
Accruals			10		14
Payments			(10)		(7)
Balance, end of period	0	7	0	7
Asset Impairment Charges [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period
Accruals			5		4
Payments			0		(4)
Balance, end of period	$ 5	$ 0	$ 5	$ 0