v3.25.4
Pensions and other benefit plans - Narrative (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 28, 2025
Dec. 29, 2024
Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items]      
Percentage of corridor of greater of market value of assets 10.00%    
Accumulated benefit obligation unfunded plans $ 3,000 $ 5,800  
Projected benefit obligation, unfunded plans 3,100 6,100  
Plan with accumulated benefit obligation in excess of plan assets, plan assets 300 3,200  
Fair value of company's common stock directly held in plan assets 17 13  
Retirement Plans      
Defined Benefit Plan Disclosure [Line Items]      
Plan Assets 36,658 33,395 $ 33,607
Other Benefit Plans      
Defined Benefit Plan Disclosure [Line Items]      
Plan Assets 99 93 $ 86
U.S. Plans      
Defined Benefit Plan Disclosure [Line Items]      
Contribution to pension plans 138    
International Plans      
Defined Benefit Plan Disclosure [Line Items]      
Contribution to pension plans 106    
Commingled funds | Level 2 | Other Benefit Plans      
Defined Benefit Plan Disclosure [Line Items]      
Plan Assets $ 99 $ 93  
Maximum | Retirement Plans      
Defined Benefit Plan Disclosure [Line Items]      
Retirement plan benefits employee compensation period 5 years