Comprehensive Income and Shareholders' Equity (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			$ 25,413	$ 21,540
Cumulative effect of accounting changes					$ 30
Other comprehensive income (loss) before reclassifications			(412)
Amounts reclassified from accumulated other comprehensive items			12
Total other comprehensive items	$ (449)	$ 217	(400)	380
Balance	26,445	22,391	26,445	22,391
Currency Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(1,755)
Cumulative effect of accounting changes					(54)
Other comprehensive income (loss) before reclassifications			(415)
Total other comprehensive items			(415)
Balance	(2,224)		(2,224)
Unrealized Gains on Available-for-Sale Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(1)
Cumulative effect of accounting changes					1
Total other comprehensive items			0
Balance	0		0
Unrealized Losses on Hedging Instruments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(50)
Cumulative effect of accounting changes					(11)
Amounts reclassified from accumulated other comprehensive items			4
Total other comprehensive items			4
Balance	(57)		(57)
Pension and Other Postretirement Benefit Liability Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(197)
Cumulative effect of accounting changes					(24)
Other comprehensive income (loss) before reclassifications			3
Amounts reclassified from accumulated other comprehensive items			8
Total other comprehensive items			11
Balance	(210)		(210)
Accumulated Other Comprehensive Items [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance			(2,003)	(2,636)
Cumulative effect of accounting changes					$ (88)
Total other comprehensive items			(400)	380
Balance	$ (2,491)	$ (2,256)	$ (2,491)	$ (2,256)