Derivatives Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2018	Apr. 01, 2017	Mar. 31, 2018	Apr. 01, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Changes in value of hedged interest rate caps, net of tax of $0.3 and $(4.6) for the three and six months ended March 31, 2018 and $0.3 and $0.7 for the three and six months ended April 1, 2017:		$ 0.4		$ 1.1
Interest rate cap - derivative
Derivative Instruments, Gain (Loss) [Line Items]
Changes in value of hedged interest rate caps, net of tax of $0.3 and $(4.6) for the three and six months ended March 31, 2018 and $0.3 and $0.7 for the three and six months ended April 1, 2017:	$ 0.7	$ 0.4	$ (3.6)	$ 1.1

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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