Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		$ 2,159.8	$ 2,115.7	$ 2,428.8
Changes in foreign currency translation adjustment	$ 1.4	(2.4)	4.3	(3.2)
Other comprehensive income (loss) before reclassifications	(4.7)	(2.1)	(25.9)	(7.5)
Ending balance	2,255.1	2,216.5	2,255.1	2,216.5
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(38.5)	(27.4)	(41.4)	(26.6)
Changes in foreign currency translation adjustment	1.4	(2.4)	4.3	(3.2)
Amounts reclassified to statement of income	0.0	0.0	0.0	0.0
Ending balance	(37.1)	(29.8)	(37.1)	(29.8)
Pension Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(1.7)	(1.1)	(1.7)	(1.1)
Other comprehensive income (loss) before reclassifications	0.0	0.0	0.0	0.0
Amounts reclassified to statement of income	0.0	0.0	0.0	0.0
Ending balance	(1.7)	(1.1)	(1.7)	(1.1)
Total
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(58.9)	(30.5)	(42.3)	(25.5)
Other comprehensive income (loss) before reclassifications		(4.5)		(10.7)
Amounts reclassified to statement of income	(0.3)	0.8	(2.0)	2.0
Other comprehensive income (loss) before reclassifications	(3.3)		(21.6)
Ending balance	(61.9)	(34.2)	(61.9)	(34.2)
Interest rate caps - derivative | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(1.1)	(2.0)	(2.7)	2.2
Other comprehensive income (loss) before reclassifications	(0.1)	(2.1)	(0.2)	(7.5)
Amounts reclassified to statement of income	(0.3)	(0.8)	(2.0)	(2.0)
Ending balance	(0.9)	$ (3.3)	(0.9)	$ (3.3)
Interest Rate Swap [Member] | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(17.6)		3.5
Other comprehensive income (loss) before reclassifications	(4.6)		(25.7)
Amounts reclassified to statement of income	0.0		0.0
Ending balance	$ (22.2)		$ (22.2)