Financial Instruments - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Sep. 27, 2025	Sep. 28, 2024
Marketable Securities [Line Items]
Cash, Cash Equivalents and Marketable Securities, Adjusted Cost	$ 134,711	$ 160,600
Cash Equivalents and Marketable Securities, Unrealized Gains	736	688
Cash Equivalents and Marketable Securities, Unrealized Loss	(3,027)	(4,638)
Cash, Cash Equivalents and Marketable Securities, Fair Value	132,420	156,650
Cash and Cash Equivalents	35,934	29,943
Current Marketable Securities	18,763	35,228
Non-Current Marketable Securities	77,723	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		2,600
Current marketable securities held in escrow and restricted from general use		13,200
Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	5,951	1,293
Marketable Securities, Equity, Unrealized Gains	177	105
Marketable Securities, Equity, Unrealized Losses	(2)	(3)
Marketable Securities, Equity, Fair Value	6,126	1,395
Cash and Cash Equivalents	5,272	778
Current Marketable Securities	854	617
Non-Current Marketable Securities	0	0
Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	100,493	132,108
Marketable Securities, Debt, Unrealized Gains	559	583
Marketable Securities, Debt, Unrealized Losses	(3,025)	(4,635)
Marketable Securities, Debt, Fair Value	98,027	128,056
Cash and Cash Equivalents	2,395	1,966
Current Marketable Securities	17,909	34,611
Non-Current Marketable Securities	77,723	91,479
Cash
Marketable Securities [Line Items]
Cash	28,267	27,199
Cash and Cash Equivalents	28,267	27,199
Money market funds | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	5,272	778
Marketable Securities, Equity, Unrealized Gains	0	0
Marketable Securities, Equity, Unrealized Losses	0	0
Marketable Securities, Equity, Fair Value	5,272	778
Cash and Cash Equivalents	5,272	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	679	515
Marketable Securities, Equity, Unrealized Gains	177	105
Marketable Securities, Equity, Unrealized Losses	(2)	(3)
Marketable Securities, Equity, Fair Value	854	617
Cash and Cash Equivalents	0	0
Current Marketable Securities	854	617
Non-Current Marketable Securities	0	0
U.S. Treasury securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	16,074	16,150
Marketable Securities, Debt, Unrealized Gains	56	45
Marketable Securities, Debt, Unrealized Losses	(282)	(516)
Marketable Securities, Debt, Fair Value	15,848	15,679
Cash and Cash Equivalents	1,190	212
Current Marketable Securities	3,712	4,087
Non-Current Marketable Securities	10,946	11,380
U.S. agency securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	5,269	5,431
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(149)	(272)
Marketable Securities, Debt, Fair Value	5,120	5,159
Cash and Cash Equivalents	251	155
Current Marketable Securities	2,456	703
Non-Current Marketable Securities	2,413	4,301
Non-U.S. government securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	6,586	17,959
Marketable Securities, Debt, Unrealized Gains	111	93
Marketable Securities, Debt, Unrealized Losses	(424)	(484)
Marketable Securities, Debt, Fair Value	6,273	17,568
Cash and Cash Equivalents	0	1,158
Current Marketable Securities	855	10,810
Non-Current Marketable Securities	5,418	5,600
Certificates of deposit and time deposits | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	917	873
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	0	0
Marketable Securities, Debt, Fair Value	917	873
Cash and Cash Equivalents	904	387
Current Marketable Securities	0	478
Non-Current Marketable Securities	13	8
Commercial paper | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	100	1,066
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	0	0
Marketable Securities, Debt, Fair Value	100	1,066
Cash and Cash Equivalents	50	28
Current Marketable Securities	50	1,038
Non-Current Marketable Securities	0	0
Corporate debt securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	47,210	65,622
Marketable Securities, Debt, Unrealized Gains	266	270
Marketable Securities, Debt, Unrealized Losses	(916)	(1,953)
Marketable Securities, Debt, Fair Value	46,560	63,939
Cash and Cash Equivalents	0	26
Current Marketable Securities	10,623	16,027
Non-Current Marketable Securities	35,937	47,886
Municipal securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	207	412
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(2)	(7)
Marketable Securities, Debt, Fair Value	205	405
Cash and Cash Equivalents	0	0
Current Marketable Securities	119	190
Non-Current Marketable Securities	86	215
Mortgage- and asset-backed securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	24,130	24,595
Marketable Securities, Debt, Unrealized Gains	126	175
Marketable Securities, Debt, Unrealized Losses	(1,252)	(1,403)
Marketable Securities, Debt, Fair Value	23,004	23,367
Cash and Cash Equivalents	0	0
Current Marketable Securities	94	1,278
Non-Current Marketable Securities	$ 22,910	$ 22,089