Restructuring and Other Costs (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period			$ 31
Accruals	10	28	20	28	28
Payments			(23)		(13)
Balance, end of period	28	15	28	15	31
Severance Benefits and Related Costs [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period			31
Accruals			7		17
Payments			(17)		(4)
Balance, end of period	21	13	21	13	31
Professional Fees [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period
Accruals			8		8
Payments			(6)		(6)
Balance, end of period	2	2	2	2
Asset Impairment Charges [Member]
Restructuring Cost and Reserve [Line Items]
Balance, beginning of period
Accruals			5		3
Payments			0		(3)
Balance, end of period	$ 5	$ 0	$ 5	$ 0