Segment Information - Information by Reportable Segment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 28, 2026	Mar. 29, 2025	Mar. 28, 2026	Mar. 29, 2025
Segment Reporting Information [Line Items]
Net sales	$ 111,184	$ 95,359	$ 254,940	$ 219,659
Cost of sales	(56,403)	(50,492)	(130,928)	(116,517)
Research and development	(11,419)	(8,550)	(22,306)	(16,818)
Selling and marketing	(5,201)	(4,731)	(10,598)	(9,832)
General and administrative	(2,276)	(1,997)	(4,371)	(4,071)
Operating income	35,885	29,589	86,737	72,421
Corporate non-segment
Segment Reporting Information [Line Items]
Research and development	(11,419)	(8,550)	(22,306)	(16,818)
General and administrative	(2,276)	(1,997)	(4,371)	(4,071)
Operating income	(13,695)	(10,547)	(26,677)	(20,889)
Americas | Operating segments
Segment Reporting Information [Line Items]
Net sales	45,093	40,315	103,622	92,963
Cost of sales	(23,114)	(21,094)	(54,963)	(49,589)
Selling and marketing	(2,606)	(2,447)	(5,333)	(5,091)
Operating income	19,373	16,774	43,326	38,283
Europe | Operating segments
Segment Reporting Information [Line Items]
Net sales	28,055	24,454	66,201	58,315
Cost of sales	(13,756)	(13,025)	(32,817)	(31,068)
Selling and marketing	(1,247)	(1,113)	(2,542)	(2,324)
Operating income	13,052	10,316	30,842	24,923
Greater China | Operating segments
Segment Reporting Information [Line Items]
Net sales	20,497	16,002	46,023	34,515
Cost of sales	(10,633)	(8,794)	(23,663)	(18,553)
Selling and marketing	(675)	(582)	(1,379)	(1,176)
Operating income	9,189	6,626	20,981	14,786
Japan | Operating segments
Segment Reporting Information [Line Items]
Net sales	8,401	7,298	17,814	16,285
Cost of sales	(4,267)	(3,610)	(8,778)	(8,003)
Selling and marketing	(295)	(254)	(584)	(534)
Operating income	3,839	3,434	8,452	7,748
Rest of Asia Pacific | Operating segments
Segment Reporting Information [Line Items]
Net sales	9,138	7,290	21,280	17,581
Cost of sales	(4,633)	(3,969)	(10,707)	(9,304)
Selling and marketing	(378)	(335)	(760)	(707)
Operating income	$ 4,127	$ 2,986	$ 9,813	$ 7,570