Accumulated Other Comprehensive Income/(Losses) Components of and Changes in Accumulated Other Comprehensive Income/(Losses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			$ (1,054)
Foreign currency translation adjustments	$ (146)	$ 421	(817)	$ 1,179
Net deferred gains/(losses) on net investment hedges	13	(124)	158	(327)
Amounts excluded from the effectiveness assessment of net investment hedges	3	0	3	0
Net deferred losses/(gains) on net investment hedges reclassified to net income	(2)	0	(2)	0
Net deferred gains/(losses) on cash flow hedges	(16)	(70)	40	(136)
Net deferred losses/(gains) on cash flow hedges reclassified to net income	12	51	(10)	97
Net postemployment benefit losses/(gains) reclassified to net income	(58)	(51)	(133)	(260)
Ending balance	(1,732)		(1,732)
Foreign Currency Translation Adjustments Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(1,587)
Foreign currency translation adjustments			(804)
Net deferred gains/(losses) on net investment hedges			158
Amounts excluded from the effectiveness assessment of net investment hedges			3
Net deferred losses/(gains) on net investment hedges reclassified to net income			(2)
Net deferred gains/(losses) on cash flow hedges			0
Net deferred losses/(gains) on cash flow hedges reclassified to net income			0
Net postemployment benefit gains/(losses) arising during the period			0
Net postemployment benefit losses/(gains) reclassified to net income			0
Total other comprehensive income/(loss)			(645)
Ending balance	(2,232)		(2,232)
Net Postemployment Benefit Plan Adjustments Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			549
Foreign currency translation adjustments			0
Net deferred gains/(losses) on net investment hedges			0
Amounts excluded from the effectiveness assessment of net investment hedges			0
Net deferred losses/(gains) on net investment hedges reclassified to net income			0
Net deferred gains/(losses) on cash flow hedges			0
Net deferred losses/(gains) on cash flow hedges reclassified to net income			0
Net postemployment benefit gains/(losses) arising during the period			70
Net postemployment benefit losses/(gains) reclassified to net income			(133)
Total other comprehensive income/(loss)			(63)
Ending balance	486		486
Net Cash Flow Hedge Adjustments Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(16)
Foreign currency translation adjustments			0
Net deferred gains/(losses) on net investment hedges			0
Amounts excluded from the effectiveness assessment of net investment hedges			0
Net deferred losses/(gains) on net investment hedges reclassified to net income			0
Net deferred gains/(losses) on cash flow hedges			40
Net deferred losses/(gains) on cash flow hedges reclassified to net income			(10)
Net postemployment benefit gains/(losses) arising during the period			0
Net postemployment benefit losses/(gains) reclassified to net income			0
Total other comprehensive income/(loss)			30
Ending balance	14		14
AOCI Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance			(1,054)
Foreign currency translation adjustments	(144)	421	(804)	1,181
Net deferred gains/(losses) on net investment hedges	13	(124)	158	(327)
Amounts excluded from the effectiveness assessment of net investment hedges	3	0	3	0
Net deferred losses/(gains) on net investment hedges reclassified to net income	(2)	0	(2)	0
Net deferred gains/(losses) on cash flow hedges	(16)	(70)	40	(136)
Net deferred losses/(gains) on cash flow hedges reclassified to net income	12	51	(10)	97
Net postemployment benefit gains/(losses) arising during the period			70
Net postemployment benefit losses/(gains) reclassified to net income	(58)	$ (51)	(133)	$ (260)
Total other comprehensive income/(loss)			(678)
Ending balance	$ (1,732)		$ (1,732)