Pension and Other Benefit Programs - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Oct. 02, 2021	Oct. 03, 2020	Sep. 28, 2019
Defined Benefit Plan Disclosure [Line Items]
New vesting service year requirement effective January 1, 2012	3 years
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Increase (Decrease) for Plan Amendment	$ 260
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	350
Pension plans with accumulated benefit obligations in excess of plan assets, projected benefit obligation	9,000	$ 19,500
Pension plans with accumulated benefit obligations in excess of plan assets, accumulated benefit obligation	8,500	18,100
Pension plans with accumulated benefit obligations in excess of plan assets, aggregate fair value of plan assets	6,900	14,400
Total accumulated pension benefit obligations	$ 19,400	$ 19,100
Total accumulated pension benefit obligations, vested percentage	98.00%	98.00%
Additional Capital Contributions Commitment	$ 1,200
Pension and postretirement medical plans, employer contributions	$ 612
Defined contribution plan, contribution rate	50.00%
Savings and investment plans, employees contribution rate	50.00%
Defined contribution plans, employer contributions	$ 254	$ 242	$ 233
Minimum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 100
Defined contribution plan, contribution rate	4.00%
Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 150
Defined contribution plan, contribution rate	10.00%
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	$ 579	410	232
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	19,900	19,800
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	16,900	14,600
Pension and postretirement medical plans, employer contributions	565	664
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	32	23	$ 19
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation	2,100	2,100
Defined Benefit Plan, Pension Plan with Projected Benefit Obligation in Excess of Plan Assets, Plan Assets	900	800
Pension and postretirement medical plans, employer contributions	$ 47	$ 9
Defined Benefit Plan, Health Care Cost Trend Rate Assumed, Next Fiscal Year	7.00%	7.00%	7.00%
Rate of increase to which the cost of benefits is assumed to decline (the ultimate trend rate)	4.00%	4.25%	4.25%