Restructuring and Other Charges - Activity and Reserve Balances for Restructuring Charges (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2012
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	$ 111	$ 134
Cash payments	(43)	(57)
Restructuring charges	212	60
Other	(162)	(26)
Restructuring reserve ending balance	118	111
Layoff Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	59	77
Cash payments	(35)	(44)
Restructuring charges	135	47
Other	(87)	(21)
Restructuring reserve ending balance	72	59
Other Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	52	57
Cash payments	(8)	(13)
Restructuring charges	77	13
Other	(75)	(5)
Restructuring reserve ending balance	$ 46	$ 52