Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 25, 2016	Jun. 27, 2015	Jun. 25, 2016	Jun. 27, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 84.8	$ 29.4	$ 238.7	$ 106.5
Changes in foreign currency translation adjustment	(3.8)	4.5	(9.2)	(14.0)
Changes in unrealized holding gains and losses on available-for-sale securities:	0.0	(0.7)	(1.2)	(3.9)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	0.0	0.0	(7.2)	0.0
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax, Portion Attributable to Parent	0.0		0.0	0.1
Changes in value of hedged interest rate caps, net of tax of $0.9 and $2.1 for the three and nine months ended June 25, 2016 and $0.5 and $1.4 for the three and nine months ended June 27, 2015:	(1.5)	(0.7)	(3.4)	(2.3)
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, Net of Tax	1.2	0.0	2.2	0.0
Other comprehensive income (loss)	(4.1)	3.1	(18.8)	(20.1)
Comprehensive income	$ 80.7	$ 32.5	$ 219.9	$ 86.4