Accumulated Other Comprehensive Loss, Excluding Noncontrolling Interests (Detail) $ in Millions	9 Months Ended
	Oct. 01, 2017 USD ($)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	$ 59,544	[1]
Balance, October 1, 2017	60,770	[1]
Foreign currency translation adjustments attributable to noncontrolling interests	16
Accumulated Other Comprehensive Income (Loss) [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	(11,036)
Other comprehensive income/(loss)	1,872	[2]
Balance, October 1, 2017	(9,164)
Foreign Currency Translation Adjustment [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	(6,659)
Other comprehensive income/(loss)	1,638	[2]
Balance, October 1, 2017	(5,021)
Derivative Financial Instruments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	348
Other comprehensive income/(loss)	(403)	[2]
Balance, October 1, 2017	(55)
Cash flow hedge loss to be reclassified within twelve months	154
Available-For-Sale Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	(131)
Other comprehensive income/(loss)	470	[2]
Balance, October 1, 2017	339
Actuarial Gains/(Losses) [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	(5,473)
Other comprehensive income/(loss)	263	[2]
Balance, October 1, 2017	(5,210)
Prior Service (Costs)/Credits and Other [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, December 31, 2016	879
Other comprehensive income/(loss)	(96)	[2]
Balance, October 1, 2017	$ 783

[1] Amounts may not add due to rounding.

[2] Amounts do not include foreign currency translation adjustments attributable to noncontrolling interests of $16 million income for the first nine months of 2017.