Restructuring and Other Charges - Activity and Reserve Balances for Restructuring Charges (Detail) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	$ 250	$ 132
Cash payments	(129)	(123)
Restructuring charges	75	532
Other	(30)	(291)
Restructuring reserve ending balance	166	250
Layoff Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	226	98
Cash payments	(107)	(111)
Restructuring charges	34	299
Other	(31)	(60)
Restructuring reserve ending balance	122	226
Other Exit Costs [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring reserve beginning balance	24	34
Cash payments	(22)	(12)
Restructuring charges	41	233
Other	1	(231)
Restructuring reserve ending balance	$ 44	$ 24