Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Sep. 30, 2019
Financial assets:
Cash equivalents	$ 93,909	$ 108,020
Marketable securities:	57,788	57,435
Forward contracts	2,372	3,064
Financial assets, fair value	154,069	168,519
Financial liabilities:
Forward contracts	1,684	2,771
Financial liabilities, fair value	1,684	2,771
Corporate notes/bonds
Financial assets:
Marketable securities:	56,288	56,436
Level 1
Financial assets:
Cash equivalents	93,909	108,020
Financial assets, fair value	150,197	164,456
Level 1 \| Corporate notes/bonds
Financial assets:
Marketable securities:	56,288	56,436
Level 2
Financial assets:
Forward contracts	2,372	3,064
Financial assets, fair value	3,872	4,063
Financial liabilities:
Forward contracts	1,684	2,771
Financial liabilities, fair value	1,684	2,771
Commercial paper
Financial assets:
Marketable securities:	1,500	999
Commercial paper \| Level 2
Financial assets:
Marketable securities:	$ 1,500	$ 999

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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