Pension, Retiree Medical and Savings Plans (Categorized Plan Assets Measured at Fair Value) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 25, 2021	Dec. 26, 2020
Defined Benefit Plan Disclosure [Line Items]
Maximum Real estate notice period	90 days
Minimum Real estate notice period	45 days
US Plan Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 11,344	$ 16,203
Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	3,195	4,624	$ 4,303
United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	11,148	15,904	15,465
Postretirement Health Coverage [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 196	$ 299	$ 315
Defined Benefit Plan, Equity Securities, Large Cap [Member]
Defined Benefit Plan Disclosure [Line Items]
Representation of one fund in total U.S. plan assets	10.00%	11.00%
Fixed Income Commingled funds [Member] | Level 1 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 628	$ 632
Mortgage-backed Securities, Issued by Private Enterprises [Member] | Level 2 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	142	199
US Government Agencies Debt Securities [Member] | Level 2 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,751	2,523
Corporate Bonds [Member] | Level 2 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	254	400
Corporate Bonds [Member] | Level 2 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	4,245	6,210
Government Securities | Level 2 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	736	$ 1,053
Corporate Bonds
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Investment within Plan Asset Category, Percentage		32.00%
Contracts With Insurance Companies | Level 3 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	27	$ 43
Contracts With Insurance Companies | Level 3 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	9	9
Cash And Cash Equivalents | Level 1 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	75	34
Cash And Cash Equivalents | Level 1 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount		216
Cash And Cash Equivalents | Level 2 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	157	136
Cash And Cash Equivalents | Fair Value, Inputs, Level 1, 2 and 3 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	157	352
Real Estate Funds [Member] | Fair Value Measured at Net Asset Value Per Share | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	173	221
Real Estate Funds [Member] | Fair Value Measured at Net Asset Value Per Share | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	533	478
Dividends And Interest Receivable | Fair Value Measured at Net Asset Value Per Share | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	11	9
Dividends And Interest Receivable | Fair Value Measured at Net Asset Value Per Share | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	120	45
Equity Securities [Member] | Level 1 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	4,387	6,387
Equity Securities [Member] | Fair Value, Inputs, Level 1, 2 and 3 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	1,291	2,232
Sub-Total U.S. Plan Assets | Fair Value, Inputs, Level 1, 2 and 3 | United States Pension Plan of US Entity, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	10,691	15,680
Sub-Total International Plan Assets | Fair Value, Inputs, Level 1, 2 and 3 | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Amount	$ 3,011	$ 4,394