Financial Instruments - Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Millions	Mar. 29, 2025	Sep. 28, 2024
Marketable Securities [Line Items]
Cash, Cash Equivalents and Marketable Securities, Adjusted Cost	$ 137,088	$ 160,600
Cash Equivalents and Marketable Securities, Unrealized Gains	376	688
Cash Equivalents and Marketable Securities, Unrealized Losses	(4,542)	(4,638)
Cash, Cash Equivalents and Marketable Securities, Fair Value	132,922	156,650
Cash and Cash Equivalents	28,162	29,943
Current Marketable Securities	20,336	35,228
Non-Current Marketable Securities	84,424	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	1,744	1,293
Marketable Securities, Equity, Unrealized Gains	81	105
Marketable Securities, Equity, Unrealized Losses	(11)	(3)
Marketable Securities, Equity, Fair Value	1,814	1,395
Cash and Cash Equivalents	1,132	778
Current Marketable Securities	682	617
Non-Current Marketable Securities	0	0
Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	110,283	132,108
Marketable Securities, Debt, Unrealized Gains	295	583
Marketable Securities, Debt, Unrealized Losses	(4,531)	(4,635)
Marketable Securities, Debt, Fair Value	106,047	128,056
Cash and Cash Equivalents	1,969	1,966
Current Marketable Securities	19,654	34,611
Non-Current Marketable Securities	84,424	91,479
Cash
Marketable Securities [Line Items]
Cash	25,061	27,199
Cash and Cash Equivalents	25,061	27,199
Money market funds | Level 1
Marketable Securities [Line Items]
Marketable Securities, Equity, Adjusted Cost	1,132	778
Marketable Securities, Equity, Unrealized Gains	0	0
Marketable Securities, Equity, Unrealized Losses	0	0
Marketable Securities, Equity, Fair Value	1,132	778
Cash and Cash Equivalents	1,132	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	612	515
Marketable Securities, Equity, Unrealized Gains	81	105
Marketable Securities, Equity, Unrealized Losses	(11)	(3)
Marketable Securities, Equity, Fair Value	682	617
Cash and Cash Equivalents	0	0
Current Marketable Securities	682	617
Non-Current Marketable Securities	0	0
U.S. Treasury securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	14,509	16,150
Marketable Securities, Debt, Unrealized Gains	24	45
Marketable Securities, Debt, Unrealized Losses	(445)	(516)
Marketable Securities, Debt, Fair Value	14,088	15,679
Cash and Cash Equivalents	124	212
Current Marketable Securities	4,088	4,087
Non-Current Marketable Securities	9,876	11,380
U.S. agency securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	4,889	5,431
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(233)	(272)
Marketable Securities, Debt, Fair Value	4,656	5,159
Cash and Cash Equivalents	66	155
Current Marketable Securities	2,004	703
Non-Current Marketable Securities	2,586	4,301
Non-U.S. government securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	6,351	17,959
Marketable Securities, Debt, Unrealized Gains	29	93
Marketable Securities, Debt, Unrealized Losses	(625)	(484)
Marketable Securities, Debt, Fair Value	5,755	17,568
Cash and Cash Equivalents	0	1,158
Current Marketable Securities	529	10,810
Non-Current Marketable Securities	5,226	5,600
Certificates of deposit and time deposits | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	1,744	873
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	0	0
Marketable Securities, Debt, Fair Value	1,744	873
Cash and Cash Equivalents	1,731	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	2	1,066
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	0	0
Marketable Securities, Debt, Fair Value	2	1,066
Cash and Cash Equivalents	0	28
Current Marketable Securities	2	1,038
Non-Current Marketable Securities	0	0
Corporate debt securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	55,743	65,622
Marketable Securities, Debt, Unrealized Gains	121	270
Marketable Securities, Debt, Unrealized Losses	(1,672)	(1,953)
Marketable Securities, Debt, Fair Value	54,192	63,939
Cash and Cash Equivalents	48	26
Current Marketable Securities	12,412	16,027
Non-Current Marketable Securities	41,732	47,886
Municipal securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	303	412
Marketable Securities, Debt, Unrealized Gains	0	0
Marketable Securities, Debt, Unrealized Losses	(5)	(7)
Marketable Securities, Debt, Fair Value	298	405
Cash and Cash Equivalents	0	0
Current Marketable Securities	170	190
Non-Current Marketable Securities	128	215
Mortgage- and asset-backed securities | Level 2
Marketable Securities [Line Items]
Marketable Securities, Debt, Adjusted Cost	26,742	24,595
Marketable Securities, Debt, Unrealized Gains	121	175
Marketable Securities, Debt, Unrealized Losses	(1,551)	(1,403)
Marketable Securities, Debt, Fair Value	25,312	23,367
Cash and Cash Equivalents	0	0
Current Marketable Securities	449	1,278
Non-Current Marketable Securities	$ 24,863	$ 22,089