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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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.

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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
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Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended
Revenue Recognition (Details) - USD ($) $ in Millions	Dec. 27, 2019	Dec. 28, 2018	Sep. 27, 2019
Disaggregation of Revenue [Line Items]
Contract with Customer, Refund Liability	$ 35.9		$ 38.5
Document Period End Date	Dec. 27, 2019
Revenues	$ 896.1	$ 972.0
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenues	590.4	600.1
CHINA
Disaggregation of Revenue [Line Items]
Revenues	168.4	194.5
KOREA, REPUBLIC OF
Disaggregation of Revenue [Line Items]
Revenues	59.0	99.1
TAIWAN, PROVINCE OF CHINA
Disaggregation of Revenue [Line Items]
Revenues	42.0	40.7
EMEA [Member]
Disaggregation of Revenue [Line Items]
Revenues	30.3	32.7
Asia, Other [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 6.0	$ 4.9