Consolidated Statement of Comprehensive Income - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 129.7	$ 144.1	$ 567.9	$ 643.0
Other comprehensive income, net of tax
Fair value of investments	(0.1)	0.3	0.3	0.5
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, after Tax	0.0	0.0	0.0	0.5
Comprehensive income	$ 129.6	$ 144.4	$ 568.2	$ 644.0