Summary of Significant Accounting Policies - Schedule of Derivative Instruments in Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain (loss) on derivative	$ (1.2)	$ 11.0	$ (1.3)
Unrealized gain (loss) on derivative	3.8	(2.1)	6.6
Forward foreign currency contracts
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain (loss) on derivative	0.7	11.0	(1.3)
Unrealized gain (loss) on derivative	(0.2)	(2.2)	6.6
Foreign Exchange Option
Accumulated Other Comprehensive Income (Loss) [Line Items]
Gain (loss) on derivative	(1.9)	0.0	0.0
Unrealized gain (loss) on derivative	$ 4.0	$ 0.1	$ 0.0