Equity Changes in Accumulated Other Comprehensive Loss, Tax (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 02, 2022	Apr. 03, 2021	Apr. 02, 2022	Apr. 03, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	$ 1,714	$ 2,382	$ 1,784	$ 2,380
Unrealized gains (losses) arising during the period	4	(31)	(34)	7
Reclassifications of realized net (gains) losses to net income	(31)	(47)	(63)	(83)
AOCI Tax, Attributable to Parent, Ending Balance	1,687	2,304	1,687	2,304
Market Value Adjustments for Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	23	95	42	40
Unrealized gains (losses) arising during the period	(9)	(24)	(32)	22
Reclassifications of realized net (gains) losses to net income	5	(2)	9	7
AOCI Tax, Attributable to Parent, Ending Balance	19	69	19	69
Unrecognized Pension and  Postretirement Medical  Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	1,606	2,155	1,653	2,201
Unrealized gains (losses) arising during the period	0	(13)	(11)	(14)
Reclassifications of realized net (gains) losses to net income	(36)	(45)	(72)	(90)
AOCI Tax, Attributable to Parent, Ending Balance	1,570	2,097	1,570	2,097
Foreign Currency Translation and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	85	132	89	139
Unrealized gains (losses) arising during the period	13	6	9	(1)
Reclassifications of realized net (gains) losses to net income	0	0	0	0
AOCI Tax, Attributable to Parent, Ending Balance	$ 98	$ 138	$ 98	$ 138