Financial Instruments - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Sep. 28, 2024	Sep. 30, 2023
Marketable Securities [Line Items]
Cash, Cash Equivalents and Marketable Securities, Adjusted Cost	$ 160,600	$ 173,752
Cash Equivalents and Marketable Securities, Unrealized Gains	688	30
Cash Equivalents and Marketable Securities, Unrealized Loss	(4,638)	(11,683)
Cash, Cash Equivalents and Marketable Securities, Fair Value	156,650	162,099
Cash and Cash Equivalents	29,943	29,965
Current Marketable Securities	35,228	31,590
Non-Current Marketable Securities	91,479	100,544
Total marketable securities that were restricted from general use		13,800
Unfavorable investigation outcome, EU State Aid rules
Marketable Securities [Line Items]
Cash and cash equivalents that were restricted from general use	2,600
Total marketable securities that were restricted from general use	13,200
Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	1,293	923
Marketable Securities, Equity, Unrealized Gains	105	12
Marketable Securities, Equity, Unrealized Losses	(3)	(26)
Marketable Securities, Equity, Fair Value	1,395	909
Cash and Cash Equivalents	778	481
Current Marketable Securities	617	428
Non-Current Marketable Securities	0	0
Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	132,108	144,470
Marketable Securities, Debt, Unrealized Gains	583	18
Marketable Securities, Debt, Unrealized Losses	(4,635)	(11,657)
Marketable Securities, Debt, Fair Value	128,056	132,831
Cash and Cash Equivalents	1,966	1,125
Current Marketable Securities	34,611	31,162
Non-Current Marketable Securities	91,479	100,544
Cash
Marketable Securities [Line Items]
Cash	27,199	28,359
Cash and Cash Equivalents	27,199	28,359
Current Marketable Securities	0	0
Non-Current Marketable Securities	0	0
Money market funds | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	778	481
Marketable Securities, Equity, Unrealized Gains	0	0
Marketable Securities, Equity, Unrealized Losses	0	0
Marketable Securities, Equity, Fair Value	778	481
Cash and Cash Equivalents	778	481
Current Marketable Securities	0	0
Non-Current Marketable Securities	0	0
Mutual funds | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	515
Marketable Securities, Equity, Unrealized Gains	105
Marketable Securities, Equity, Unrealized Losses	(3)
Marketable Securities, Equity, Fair Value	617
Cash and Cash Equivalents	0
Current Marketable Securities	617
Non-Current Marketable Securities	0
Mutual funds and equity securities | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost		442
Marketable Securities, Equity, Unrealized Gains		12
Marketable Securities, Equity, Unrealized Losses		(26)
Marketable Securities, Equity, Fair Value		428
Cash and Cash Equivalents		0
Current Marketable Securities		428
Non-Current Marketable Securities		0
U.S. Treasury securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	16,150	19,406
Marketable Securities, Debt, Unrealized Gains	45	0
Marketable Securities, Debt, Unrealized Losses	(516)	(1,292)
Marketable Securities, Debt, Fair Value	15,679	18,114
Cash and Cash Equivalents	212	35
Current Marketable Securities	4,087	5,468
Non-Current Marketable Securities	11,380	12,611
U.S. agency securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	5,431	5,736
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(272)	(600)
Marketable Securities, Debt, Fair Value	5,159	5,136
Cash and Cash Equivalents	155	36
Current Marketable Securities	703	271
Non-Current Marketable Securities	4,301	4,829
Non-U.S. government securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	17,959	17,533
Marketable Securities, Debt, Unrealized Gains	93	6
Marketable Securities, Debt, Unrealized Losses	(484)	(1,048)
Marketable Securities, Debt, Fair Value	17,568	16,491
Cash and Cash Equivalents	1,158	0
Current Marketable Securities	10,810	11,332
Non-Current Marketable Securities	5,600	5,159
Certificates of deposit and time deposits | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	873	1,354
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	0	0
Marketable Securities, Debt, Fair Value	873	1,354
Cash and Cash Equivalents	387	1,034
Current Marketable Securities	478	320
Non-Current Marketable Securities	8	0
Commercial paper | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	1,066	608
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	0	0
Marketable Securities, Debt, Fair Value	1,066	608
Cash and Cash Equivalents	28	0
Current Marketable Securities	1,038	608
Non-Current Marketable Securities	0	0
Corporate debt securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	65,622	76,840
Marketable Securities, Debt, Unrealized Gains	270	6
Marketable Securities, Debt, Unrealized Losses	(1,953)	(5,956)
Marketable Securities, Debt, Fair Value	63,939	70,890
Cash and Cash Equivalents	26	20
Current Marketable Securities	16,027	12,627
Non-Current Marketable Securities	47,886	58,243
Municipal securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	412	628
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(7)	(26)
Marketable Securities, Debt, Fair Value	405	602
Cash and Cash Equivalents	0	0
Current Marketable Securities	190	192
Non-Current Marketable Securities	215	410
Mortgage- and asset-backed securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	24,595	22,365
Marketable Securities, Debt, Unrealized Gains	175	6
Marketable Securities, Debt, Unrealized Losses	(1,403)	(2,735)
Marketable Securities, Debt, Fair Value	23,367	19,636
Cash and Cash Equivalents	0	0
Current Marketable Securities	1,278	344
Non-Current Marketable Securities	$ 22,089	$ 19,292