Equity Changes in Accumulated Other Comprehensive Loss, Before Tax (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 01, 2023	Jul. 02, 2022	Jul. 01, 2023	Jul. 02, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	$ (5,396)	$ (7,999)	$ (4,980)	$ (8,224)
Unrealized gains (losses) arising during the period	41	197	(85)	151
Reclassifications of realized net (gains) losses to net income	(72)	128	(362)	399
AOCI before Tax, Attributable to Parent, Ending Balance	(5,427)	(7,674)	(5,427)	(7,674)
Market Value Adjustments for Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	2	(51)	804	(152)
Unrealized gains (losses) arising during the period	85	601	(383)	741
Reclassifications of realized net (gains) losses to net income	(73)	(27)	(407)	(66)
AOCI before Tax, Attributable to Parent, Ending Balance	14	523	14	523
Unrecognized Pension and  Postretirement Medical  Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	(3,697)	(6,668)	(3,770)	(7,025)
Unrealized gains (losses) arising during the period	0	0	71	47
Reclassifications of realized net (gains) losses to net income	1	155	3	465
AOCI before Tax, Attributable to Parent, Ending Balance	(3,696)	(6,513)	(3,696)	(6,513)
Foreign Currency Translation and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	(1,701)	(1,280)	(2,014)	(1,047)
Unrealized gains (losses) arising during the period	(44)	(404)	227	(637)
Reclassifications of realized net (gains) losses to net income	0	0	42	0
AOCI before Tax, Attributable to Parent, Ending Balance	$ (1,745)	$ (1,684)	$ (1,745)	$ (1,684)