Summary of Changes in AOCI by Component (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015		Jun. 30, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Currency translation adjustment, Beginning Balance				$ (2,323)		$ (991)
Currency translation adjustment, other comprehensive income (loss) before reclassifications				(717)		(207)
Currency translation adjustment, amounts reclassified from AOCI	[1]			0		0
Currency translation adjustment, net other comprehensive (loss) income		$ 421	$ (213)	(717)		(207)
Currency translation adjustment, Ending Balance		(3,040)	(1,198)	(3,040)		(1,198)
Pension and other employee benefit, Beginning Balance				(1,427)		(1,027)
Pension and other employee benefit, Other comprehensive income (loss) before reclassifications				114		2
Pension and other employee benefit, Amounts reclassified from AOCI	[2]	32	23	67	[1]	49	[1]
Pension and other employee benefit, Net other comprehensive (loss) income		113	28	181		51
Pension and other employee benefit, Ending Balance		(1,246)	(976)	(1,246)		(976)
Hedging activities, Beginning Balance				34		10
Hedging activities, Other comprehensive income (loss) before reclassifications				53		(5)
Hedging activities, Amounts reclassified from AOCI	[2]	(19)	1	(35)	[1]	(1)	[1]
Hedging activities, Net other comprehensive income (loss)		28	4	18		(6)
Hedging activities, Ending Balance		52	4	52		4
Other, Beginning Balance				66		32
Other, Other comprehensive income (loss) before reclassifications				24		(7)
Other, Amounts reclassified from AOCI	[2]	(9)		(2)	[1]
Other, Net other comprehensive (loss) income		1	(18)	22		(7)
Other, Ending Balance		88	25	88		25
Total, Beginning Balance				(3,650)		(1,976)
Total, Other comprehensive income (loss) before reclassifications				(526)		(217)
Total, Amounts reclassified from AOCI	[2]	4	24	30	[1]	48	[1]
Total other comprehensive income (loss), net of tax		563	(199)	(496)		(169)
Total, Ending Balance		$ (4,146)	$ (2,145)	$ (4,146)		$ (2,145)

[1] See table below for details about these reclassifications.

[2] Amounts in parentheses indicate reductions to net income.