Consolidated Statements Of Operations - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 28, 2019	Jun. 29, 2018	Jun. 28, 2019	Jun. 29, 2018
Income Statement [Abstract]
Net revenue	$ 767.0	$ 894.3	$ 2,549.4	$ 2,859.6
Cost of goods sold	454.5	442.7	1,351.6	1,412.5
Gross profit	312.5	451.6	1,197.8	1,447.1
Operating expenses:
Research and development	100.6	96.8	317.3	301.5
Selling, general and administrative	46.8	44.6	142.5	153.4
Amortization of intangibles	5.5	3.9	18.6	12.0
Restructuring and other charges	0.0	0.0	1.3	1.0
Total operating expenses	152.9	145.3	479.7	467.9
Operating income	159.6	306.3	718.1	979.2
Other income, net	2.3	4.5	8.9	9.5
Income before income taxes	161.9	310.8	727.0	988.7
Provision for income taxes	17.8	24.3	84.0	355.8
Net income	$ 144.1	$ 286.5	$ 643.0	$ 632.9
Earnings per share:
Basic (in dollars per share)	$ 0.83	$ 1.58	$ 3.69	$ 3.47
Diluted (in dollars per share)	$ 0.83	$ 1.57	$ 3.67	$ 3.44
Weighted average shares:
Basic (in shares)	172.6	181.2	174.3	182.3
Diluted (in shares)	173.4	182.8	175.2	184.2
Cash dividends declared and paid per share (usd per share)	$ 0.38	$ 0.32	$ 1.14	$ 0.96