Pension, Retiree Medical and Savings Plans (Selected Financial Information for Pension and Retiree Medical Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Pension Plans, Defined Benefit
Change in fair value of plan assets
Employer contributions/funding	$ 1,400	$ 164	$ 659
Retiree Medical Plan
Change in projected benefit liability
Liability at beginning of year	1,187	1,208
Service cost	32	28	31
Interest cost	34	36	41
Plan amendments		(5)
Experience (gain)/loss	(147)	21
Special termination benefits	1	2
Other, including foreign currency adjustment	(3)	4
Liability at end of year	996	1,187	1,208
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(108)	(107)
Change in fair value of plan assets
Fair value at beginning of year	321	320
Defined Benefit Plan, Plan Assets, Benefits Paid	(108)	(107)
Actual return on plan assets	(21)	52
Employer contributions/funding	93	56	36
Fair value at end of year	285	321	320
Funded status	(711)	(866)
Amounts recognized
Other current liabilities	(41)	(75)
Other liabilities	(670)	(791)
Net amount recognized	(711)	(866)
Amounts included in accumulated other comprehensive loss (pre-tax)
Net loss/(gain)	(287)	(189)
Prior service cost/(credit)	(51)	(71)
Total	(338)	(260)
Changes recognized in net loss/(gain) included in other comprehensive loss
Net loss/(gain) arising in current year	(107)	(9)
Amortization and settlement recognition	8	12
Foreign currency translation (gain)/loss	1	1
Total	(98)	4
Domestic Plan [Member]
Change in projected benefit liability
Liability at beginning of year	14,777	13,192
Service cost	431	401	393
Interest cost	482	468	484
Plan amendments	83	10
Experience (gain)/loss	(972)	1,529
Settlement/curtailment	(74)	(58)
Special termination benefits	36	60
Liability at end of year	13,807	14,777	13,192
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(956)	(825)
Change in fair value of plan assets
Fair value at beginning of year	12,582	11,458
Defined Benefit Plan, Plan Assets, Benefits Paid	(956)	(825)
Actual return on plan assets	(789)	1,935
Employer contributions/funding	1,495	60
Defined Benefit Plan, Plan Assets, Payment for Settlement	(74)	(46)
Fair value at end of year	12,258	12,582	11,458
Funded status	(1,549)	(2,195)
Amounts recognized
Other assets	185	286
Other current liabilities	(107)	(74)
Other liabilities	(1,627)	(2,407)
Net amount recognized	(1,549)	(2,195)
Amounts included in accumulated other comprehensive loss (pre-tax)
Net loss/(gain)	4,093	3,520
Prior service cost/(credit)	109	29
Total	4,202	3,549
Changes recognized in net loss/(gain) included in other comprehensive loss
Net loss/(gain) arising in current year	760	431
Amortization and settlement recognition	(187)	(131)
Total	573	300
Accumulated benefit obligation at end of year	12,890	13,732
Foreign Plan [Member]
Change in projected benefit liability
Liability at beginning of year	3,490	3,124
Service cost	92	91	80
Interest cost	93	89	94
Plan amendments	2	2
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant	2	2
Experience (gain)/loss	(230)	5
Settlement/curtailment	(35)	(22)
Special termination benefits	2
Other, including foreign currency adjustment	(204)	303
Liability at end of year	3,098	3,490	3,124
Defined Benefit Plan, Benefit Obligation, Benefits Paid	(114)	(104)
Change in fair value of plan assets
Fair value at beginning of year	3,460	2,894
Defined Benefit Plan, Plan Assets, Benefits Paid	(114)	(104)
Participant contributions	2	2
Actual return on plan assets	(136)	288
Employer contributions/funding	120	104
Defined Benefit Plan, Plan Assets, Payment for Settlement	(32)	(18)
Other, including foreign currency adjustment	(210)	294
Fair value at end of year	3,090	3,460	$ 2,894
Funded status	(8)	(30)
Amounts recognized
Other assets	81	85
Other current liabilities	(1)	(1)
Other liabilities	(88)	(114)
Net amount recognized	(8)	(30)
Amounts included in accumulated other comprehensive loss (pre-tax)
Net loss/(gain)	780	782
Prior service cost/(credit)	(1)	(3)
Total	779	779
Changes recognized in net loss/(gain) included in other comprehensive loss
Net loss/(gain) arising in current year	103	(115)
Amortization and settlement recognition	(56)	(60)
Foreign currency translation (gain)/loss	(49)	73
Total	(2)	(102)
Accumulated benefit obligation at end of year	$ 2,806	$ 2,985