Equity Changes in Accumulated Other Comprehensive Loss, Tax (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	$ 2,304	$ 1,841	$ 2,380	$ 1,842
Other Comprehensive Income (Loss) before Reclassifications, Tax	(46)	49	(39)	88
Reclassification from AOCI, Current Period, Tax	(47)	(13)	(130)	(53)
AOCI Tax, Attributable to Parent, Ending Balance	2,211	1,877	2,211	1,877
Market Value Adjustments for Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	69	(36)	40	(29)
Other Comprehensive Income (Loss) before Reclassifications, Tax	0	19	22	(12)
Reclassification from AOCI, Current Period, Tax	(2)	18	5	42
AOCI Tax, Attributable to Parent, Ending Balance	67	1	67	1
Unrecognized Pension and  Postretirement Medical  Expense
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	2,097	1,702	2,201	1,756
Other Comprehensive Income (Loss) before Reclassifications, Tax	(9)	2	(23)	12
Reclassification from AOCI, Current Period, Tax	(45)	(31)	(135)	(95)
AOCI Tax, Attributable to Parent, Ending Balance	2,043	1,673	2,043	1,673
Foreign Currency Translation and Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
AOCI Tax, Attributable to Parent, Beginning Balance	138	175	139	115
Other Comprehensive Income (Loss) before Reclassifications, Tax	(37)	28	(38)	88
Reclassification from AOCI, Current Period, Tax	0	0	0	0
AOCI Tax, Attributable to Parent, Ending Balance	$ 101	$ 203	$ 101	$ 203