Equity Changes in Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 27, 2025	Sep. 28, 2024	Sep. 30, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (3,699)	$ (3,292)	$ (4,119)
Unrealized gains (losses) arising during the period	31	23	1,136
Reclassifications of realized net (gains) losses to net income	(92)	(430)	(309)
AOCI reclassifications to comprehensive income, net of tax	846
Accumulated Other Comprehensive Income (Loss), Net of Tax	(2,914)	(3,699)	(3,292)
Market Value Adjustments for Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(248)	195	625
Unrealized gains (losses) arising during the period	11	(85)	(89)
Reclassifications of realized net (gains) losses to net income	(192)	(358)	(341)
AOCI reclassifications to comprehensive income, net of tax	0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(429)	(248)	195
Accumulated other comprehensive (income) loss related to defined benefit plans.
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(1,712)	(1,655)	(2,869)
Unrealized gains (losses) arising during the period	157	15	1,210
Reclassifications of realized net (gains) losses to net income	100	(72)	4
AOCI reclassifications to comprehensive income, net of tax	0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(1,455)	(1,712)	(1,655)
Accumulated Net Gain (Loss) from Foreign Currency and Other Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(1,739)	(1,832)	(1,875)
Unrealized gains (losses) arising during the period	(137)	93	15
Reclassifications of realized net (gains) losses to net income	0	0	28
AOCI reclassifications to comprehensive income, net of tax	846
Accumulated Other Comprehensive Income (Loss), Net of Tax	$ (1,030)	$ (1,739)	$ (1,832)