Basis of Presentation - Recently adopted accounting pronouncements (Details) - USD ($) $ in Thousands		9 Months Ended
Oct. 01, 2017	Jun. 30, 2018	Jun. 30, 2017
New accounting pronouncements
Increase in cash provided by operating activities		$ 358,421	$ 240,255
Decrease in net cash used in financing activities		(231,186)	(224,451)
ASU 2016-09
New accounting pronouncements
Increase in cash provided by operating activities			4,100
Decrease in net cash used in financing activities			$ 4,100
Cumulative effect adjustment	$ 300	$ 317

Amount after tax of cumulative effect adjustment on equity or net assets for prospective application of a new accounting principle.

No definition available.

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- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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