Changes in Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 28, 2024	Dec. 30, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	$ (3,699)	$ (3,292)
Unrealized gains (losses) arising during the period	207	(84)
Reclassifications of realized net (gains) losses to net income	(42)	(126)
AOCI reclassifications to comprehensive income, net of tax	846
AOCI, Ending Balance	(2,688)	(3,502)
Market Value Adjustments for Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	(248)	195
Unrealized gains (losses) arising during the period	429	(211)
Reclassifications of realized net (gains) losses to net income	(67)	(108)
AOCI reclassifications to comprehensive income, net of tax	0
AOCI, Ending Balance	114	(124)
Unrecognized Pension and  Postretirement Medical  Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	(1,712)	(1,655)
Unrealized gains (losses) arising during the period	0	(3)
Reclassifications of realized net (gains) losses to net income	25	(18)
AOCI reclassifications to comprehensive income, net of tax	0
AOCI, Ending Balance	(1,687)	(1,676)
Foreign Currency Translation and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI, Beginning Balance	(1,739)	(1,832)
Unrealized gains (losses) arising during the period	(222)	130
Reclassifications of realized net (gains) losses to net income	0	0
AOCI reclassifications to comprehensive income, net of tax	846
AOCI, Ending Balance	$ (1,115)	$ (1,702)