The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD.

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Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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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

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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-Publisher FASB
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Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
Revenue Recognition (Details) - USD ($) $ in Millions	Jun. 26, 2020	Jun. 28, 2019	Jun. 26, 2020	Jun. 28, 2019	Sep. 27, 2019
Disaggregation of Revenue [Line Items]
Contract with Customer, Refund Liability	$ 24.2		$ 24.2		$ 38.5
Document Period End Date			Jun. 26, 2020
Revenues	736.8	$ 767.0	$ 2,398.9	$ 2,549.4
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenues	425.2	355.7	1,431.0	1,358.9
CHINA
Disaggregation of Revenue [Line Items]
Revenues	166.5	212.9	512.9	606.8
KOREA, REPUBLIC OF
Disaggregation of Revenue [Line Items]
Revenues	46.0	76.9	178.9	282.0
TAIWAN, PROVINCE OF CHINA
Disaggregation of Revenue [Line Items]
Revenues	64.9	78.0	165.9	182.8
EMEA [Member]
Disaggregation of Revenue [Line Items]
Revenues	29.0	36.5	91.9	100.2
Asia, Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 5.2	$ 7.0	$ 18.3	$ 18.7