Financial Instruments - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Dec. 28, 2024	Sep. 28, 2024
Marketable Securities [Line Items]
Cash, Cash Equivalents and Marketable Securities, Adjusted Cost	$ 147,088	$ 160,600
Cash Equivalents and Marketable Securities, Unrealized Gains	261	688
Cash Equivalents and Marketable Securities, Unrealized Losses	(5,981)	(4,638)
Cash, Cash Equivalents and Marketable Securities, Fair Value	141,368	156,650
Cash and Cash Equivalents	30,299	29,943
Current Marketable Securities	23,476	35,228
Non-Current Marketable Securities	87,593	91,479
Unfavorable investigation outcome, EU State Aid rules
Marketable Securities [Line Items]
Cash and cash equivalents held in escrow and restricted from general use	126	2,600
Current marketable securities held in escrow and restricted from general use	3,300	13,200
Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	1,534	1,293
Marketable Securities, Equity, Unrealized Gains	109	105
Marketable Securities, Equity, Unrealized Losses	(7)	(3)
Marketable Securities, Equity, Fair Value	1,636	1,395
Cash and Cash Equivalents	937	778
Current Marketable Securities	699	617
Non-Current Marketable Securities	0	0
Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	118,481	132,108
Marketable Securities, Debt, Unrealized Gains	152	583
Marketable Securities, Debt, Unrealized Losses	(5,974)	(4,635)
Marketable Securities, Debt, Fair Value	112,659	128,056
Cash and Cash Equivalents	2,289	1,966
Current Marketable Securities	22,777	34,611
Non-Current Marketable Securities	87,593	91,479
Cash
Marketable Securities [Line Items]
Cash	27,073	27,199
Cash and Cash Equivalents	27,073	27,199
Money market funds | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	937	778
Marketable Securities, Equity, Unrealized Gains	0	0
Marketable Securities, Equity, Unrealized Losses	0	0
Marketable Securities, Equity, Fair Value	937	778
Cash and Cash Equivalents	937	778
Current Marketable Securities	0	0
Non-Current Marketable Securities	0	0
Mutual funds | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	597	515
Marketable Securities, Equity, Unrealized Gains	109	105
Marketable Securities, Equity, Unrealized Losses	(7)	(3)
Marketable Securities, Equity, Fair Value	699	617
Cash and Cash Equivalents	0	0
Current Marketable Securities	699	617
Non-Current Marketable Securities	0	0
U.S. Treasury securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	15,516	16,150
Marketable Securities, Debt, Unrealized Gains	5	45
Marketable Securities, Debt, Unrealized Losses	(616)	(516)
Marketable Securities, Debt, Fair Value	14,905	15,679
Cash and Cash Equivalents	903	212
Current Marketable Securities	2,718	4,087
Non-Current Marketable Securities	11,284	11,380
U.S. agency securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	5,570	5,431
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(303)	(272)
Marketable Securities, Debt, Fair Value	5,267	5,159
Cash and Cash Equivalents	314	155
Current Marketable Securities	1,683	703
Non-Current Marketable Securities	3,270	4,301
Non-U.S. government securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	8,596	17,959
Marketable Securities, Debt, Unrealized Gains	22	93
Marketable Securities, Debt, Unrealized Losses	(819)	(484)
Marketable Securities, Debt, Fair Value	7,799	17,568
Cash and Cash Equivalents	50	1,158
Current Marketable Securities	2,524	10,810
Non-Current Marketable Securities	5,225	5,600
Certificates of deposit and time deposits | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	1,147	873
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(13)	0
Marketable Securities, Debt, Fair Value	1,134	873
Cash and Cash Equivalents	874	387
Current Marketable Securities	247	478
Non-Current Marketable Securities	13	8
Commercial paper | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	418	1,066
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(19)	0
Marketable Securities, Debt, Fair Value	399	1,066
Cash and Cash Equivalents	101	28
Current Marketable Securities	298	1,038
Non-Current Marketable Securities	0	0
Corporate debt securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	61,566	65,622
Marketable Securities, Debt, Unrealized Gains	96	270
Marketable Securities, Debt, Unrealized Losses	(2,210)	(1,953)
Marketable Securities, Debt, Fair Value	59,452	63,939
Cash and Cash Equivalents	47	26
Current Marketable Securities	14,451	16,027
Non-Current Marketable Securities	44,954	47,886
Municipal securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	355	412
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(7)	(7)
Marketable Securities, Debt, Fair Value	348	405
Cash and Cash Equivalents	0	0
Current Marketable Securities	189	190
Non-Current Marketable Securities	159	215
Mortgage- and asset-backed securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	25,313	24,595
Marketable Securities, Debt, Unrealized Gains	29	175
Marketable Securities, Debt, Unrealized Losses	(1,987)	(1,403)
Marketable Securities, Debt, Fair Value	23,355	23,367
Cash and Cash Equivalents	0	0
Current Marketable Securities	667	1,278
Non-Current Marketable Securities	$ 22,688	$ 22,089