Equity Changes in Accumulated Other Comprehensive Loss, Before Tax (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 01, 2023	Apr. 02, 2022	Apr. 01, 2023	Apr. 02, 2022
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	$ (5,484)	$ (7,990)	$ (4,980)	$ (8,224)
Unrealized gains (losses) arising during the period	203	(143)	(126)	(46)
Reclassifications of realized net (gains) losses to net income	(115)	134	(290)	271
AOCI before Tax, Attributable to Parent, Ending Balance	(5,396)	(7,999)	(5,396)	(7,999)
Market Value Adjustments for Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	111	(83)	804	(152)
Unrealized gains (losses) arising during the period	7	53	(468)	140
Reclassifications of realized net (gains) losses to net income	(116)	(21)	(334)	(39)
AOCI before Tax, Attributable to Parent, Ending Balance	2	(51)	2	(51)
Unrecognized Pension and  Postretirement Medical  Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	(3,769)	(6,823)	(3,770)	(7,025)
Unrealized gains (losses) arising during the period	71	0	71	47
Reclassifications of realized net (gains) losses to net income	1	155	2	310
AOCI before Tax, Attributable to Parent, Ending Balance	(3,697)	(6,668)	(3,697)	(6,668)
Foreign Currency Translation and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI before Tax, Attributable to Parent, Beginning Balance	(1,826)	(1,084)	(2,014)	(1,047)
Unrealized gains (losses) arising during the period	125	(196)	271	(233)
Reclassifications of realized net (gains) losses to net income	0	0	42	0
AOCI before Tax, Attributable to Parent, Ending Balance	$ (1,701)	$ (1,280)	$ (1,701)	$ (1,280)