Net Periodic Benefit Cost (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 01, 2022	Jan. 02, 2021
Defined Benefit Plan Disclosure [Line Items]
Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component	$ (16)	$ 33
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	100	108
Interest costs	124	114
Expected return on plan assets	(293)	(275)
Amortization of previously deferred service costs	1	2
Recognized net actuarial loss	147	186
Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component	(21)	27
Net periodic benefit cost	79	135
Postretirement Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Service costs	2	3
Interest costs	13	12
Expected return on plan assets	(15)	(14)
Amortization of previously deferred service costs	0	0
Recognized net actuarial loss	7	7
Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component	5	5
Net periodic benefit cost	$ 7	$ 8