v3.25.3
Pension and Other Benefit Programs - Additional Information (Detail) - USD ($)
$ in Millions
 12 Months Ended
Sep. 27, 2025
Sep. 28, 2024
Sep. 30, 2023
Defined Benefit Plan Disclosure [Line Items]      
New vesting service year requirement effective January 1, 2012 3 years    
Pension plans with accumulated benefit obligations in excess of plan assets, projected benefit obligation $ 1,300 $ 1,400  
Pension plans with accumulated benefit obligations in excess of plan assets, accumulated benefit obligation   1,300  
Total accumulated pension benefit obligations $ 15,500 $ 15,700  
Total accumulated pension benefit obligations, vested percentage 99.00% 98.00%  
Additional Capital Contributions Commitment $ 1,300    
Pension and postretirement medical plans, employer contributions $ 98    
Defined Contribution Plan, Employer Matching Contribution, Percent of Match 50.00%    
Defined contribution plans, employer contributions $ 448 $ 408 $ 378
Minimum      
Defined Benefit Plan Disclosure [Line Items]      
Defined contribution plan, contribution rate 3.00%    
Maximum      
Defined Benefit Plan Disclosure [Line Items]      
Defined contribution plan, contribution rate 9.00%    
Pension Plans      
Defined Benefit Plan Disclosure [Line Items]      
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) $ 136 (27) (56)
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation 1,400    
Pension and postretirement medical plans, employer contributions 71 69  
Postretirement Medical Plans      
Defined Benefit Plan Disclosure [Line Items]      
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) (132) (128) $ 3
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation 900 1,000  
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets   900  
Pension and postretirement medical plans, employer contributions $ 27 $ 26  
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year 7.50% 7.00% 7.00%
Rate of increase to which the cost of benefits is assumed to decline (the ultimate trend rate) 4.00% 4.00% 4.00%