Consolidated Statement of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jul. 01, 2016	Jun. 30, 2017	Jul. 01, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 246.2	$ 185.0	$ 728.9	$ 748.4
Other comprehensive income
Fair value of investments	0.0	0.0	0.9	0.0
Foreign currency translation adjustment	0.1	(0.5)	0.8	(0.8)
Comprehensive income	$ 246.3	$ 184.5	$ 730.6	$ 747.6

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831270

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=51831223

Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e557-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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