Consolidated Statements Of Cash Flows - USD ($) $ in Millions	6 Months Ended
	Mar. 29, 2019	Mar. 30, 2018
Statement of Cash Flows [Abstract]
Net income	$ 498.8	$ 346.4
Adjustments to reconcile net income to net cash provided by operating activities:
Share-based compensation	42.6	66.8
Depreciation	156.4	129.6
Amortization of intangible assets	28.6	11.1
Deferred income taxes	(27.6)	25.6
Other	0.8	0.0
Changes in assets and liabilities net of acquired balances:
Receivables, net	112.0	87.5
Inventory	(66.9)	26.3
Other current and long-term assets	(14.9)	(27.1)
Accounts payable	(23.9)	(82.2)
Other current and long-term liabilities	35.2	211.0
Net cash provided by operating activities	741.1	795.0
Cash flows from investing activities:
Capital expenditures	(226.2)	(118.5)
Payments for Software	(12.9)	(6.0)
Payments to Acquire Marketable Securities	(166.7)	0.0
Maturity of investments	309.2	0.0
Net cash used in investing activities	(96.6)	(124.5)
Cash flows from financing activities:
Repurchase of common stock - payroll tax withholdings on equity awards	(21.0)	(46.5)
Repurchase of common stock - stock repurchase program	(425.5)	(284.2)
Dividends paid	(133.1)	(117.5)
Net proceeds from exercise of stock options	6.8	32.3
Proceeds from employee stock purchase plan	11.3	9.9
Net cash used in financing activities	(561.5)	(406.0)
Net increase (decrease) in cash and cash equivalents	83.0	264.5
Cash and cash equivalents at beginning of period	733.3	1,616.8
Cash and cash equivalents at end of period	816.3	1,881.3
Supplemental cash flow disclosures:
Income taxes paid	$ 87.5	$ 76.2