Components of and Changes in Accumulated Other Comprehensive Income/(Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ 51,657
Cumulative effect of accounting standards adopted in the period			136
Total other comprehensive income/(loss)			(183)
Ending balance	$ 51,673	$ 65,219	51,673	$ 65,219
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(2,476)
Other comprehensive income/(loss) before reclassifications	(410)	(142)	(272)	(796)
Total other comprehensive income/(loss)			(119)
Ending balance	(2,595)		(2,595)
Net investment hedge adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Other comprehensive income/(loss) before reclassifications	151	13	147	158
Amounts excluded from effectiveness assessment	6	3	16	3
Reclassifications from AOCI	(6)	(2)	(10)	(2)
Net Postemployment Benefit Plan Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			492
Other comprehensive income/(loss) before reclassifications			(14)
Reclassifications from AOCI	(59)	(58)	(176)	(133)
Cumulative effect of accounting standards adopted in the period			114
Total other comprehensive income/(loss)			(76)
Ending balance	416		416
Net cash flow hedge adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			41
Other comprehensive income/(loss) before reclassifications	50	(16)	24	40
Amounts excluded from effectiveness assessment	8	0	21	0
Reclassifications from AOCI	(50)	$ 12	(55)	$ (10)
Cumulative effect of accounting standards adopted in the period			22
Total other comprehensive income/(loss)			12
Ending balance	53		53
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(1,943)
Ending balance	$ (2,126)		$ (2,126)