v3.25.2
Pension, Retiree Medical and Savings Plans (Estimated Future Benefit Payments) (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 27, 2025
Dec. 28, 2024
Dec. 30, 2023
Dec. 31, 2022
Jan. 22, 2025
Domestic Plan          
Defined Benefit Plan Disclosure [Line Items]          
Employer contributions/funding   $ 236 $ 314    
Pension Plans, Defined Benefit          
Defined Benefit Plan Disclosure [Line Items]          
Discretionary   161 267 $ 160  
Non-discretionary   134 97 176  
Defined Benefit Plan, Expected Future Benefit Payment, Year One   1,053      
Defined Benefit Plan, Expected Future Benefit Payment, Year Two   1,145      
Defined Benefit Plan, Expected Future Benefit Payment, Year Three   953      
Defined Benefit Plan, Expected Future Benefit Payment, Year Four   982      
Defined Benefit Plan, Expected Future Benefit Payment, Year Five   1,008      
Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years   5,327      
Employer contributions/funding   295 364 336  
Retiree Medical Plan          
Defined Benefit Plan Disclosure [Line Items]          
Discretionary   0 0 0  
Non-discretionary   53 46 48  
Defined Benefit Plan, Expected Future Benefit Payment, Year One   77      
Defined Benefit Plan, Expected Future Benefit Payment, Year Two   75      
Defined Benefit Plan, Expected Future Benefit Payment, Year Three   72      
Defined Benefit Plan, Expected Future Benefit Payment, Year Four   69      
Defined Benefit Plan, Expected Future Benefit Payment, Year Five   67      
Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years   295      
Employer contributions/funding   53 46 48  
us-gaap_DomesticPlanMember-Discretionary contributions          
Defined Benefit Plan Disclosure [Line Items]          
Discretionary   150 $ 250 $ 150  
Domestic plan -Plan I          
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]          
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year         $ 250
Years 2029 Through 2033          
Defined Benefit Plan Disclosure [Line Items]          
Subsidies expected to be received under the 2003 Medicare Act   2      
Maximum | Years 2024 Through 2028          
Defined Benefit Plan Disclosure [Line Items]          
Subsidies expected to be received under the 2003 Medicare Act   $ 1      
Forecast [Member] | Pension Plans, Defined Benefit          
Defined Benefit Plan Disclosure [Line Items]          
Non-discretionary $ 102        
Forecast [Member] | Retiree Medical Plan [Member]          
Defined Benefit Plan Disclosure [Line Items]          
Non-discretionary $ 52