Pension, Retiree Medical and Savings Plans (Selected Information About Plans with Liability for Service to Date and Total Benefit Liability in Excess of Plan Assets) (Details) - USD ($) $ in Millions	Dec. 28, 2019	Dec. 29, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit, Unfunded plans	$ 847
Domestic Plan [Member]
Selected information for plans with accumulated benefit obligation in excess of plan assets
Liability for service to date	(9,194)	$ (8,040)
Fair value of plan assets	8,497	7,223
Selected information for plans with projected benefit liability in excess of plan assets
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	(10,169)	(8,957)
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	8,497	7,223
Foreign Plan [Member]
Selected information for plans with accumulated benefit obligation in excess of plan assets
Liability for service to date	(192)	(155)
Fair value of plan assets	151	121
Selected information for plans with projected benefit liability in excess of plan assets
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	(632)	(514)
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	512	426
Retiree Medical Plan
Selected information for plans with projected benefit liability in excess of plan assets
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	(988)	(996)
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	$ 302	$ 285