Fair Value Measurements (Schedule of Financial Assets and Liabilities Measured at Fair Value) (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Sep. 30, 2019
Financial assets:
Cash equivalents	$ 83,044	$ 108,020
Marketable securities:	57,480	57,435
Forward contracts	757	3,064
Financial assets, fair value	141,281	168,519
Financial liabilities:
Forward contracts	1,694	2,771
Financial liabilities, fair value	1,694	2,771
Level 1
Financial assets:
Cash equivalents	83,044	108,020
Financial assets, fair value	140,524	164,456
Level 2
Financial assets:
Forward contracts	757	3,064
Financial assets, fair value	757	4,063
Financial liabilities:
Forward contracts	1,694	2,771
Financial liabilities, fair value	1,694	2,771
Commercial paper
Financial assets:
Marketable securities:		999
Commercial paper \| Level 2
Financial assets:
Marketable securities:		999
Corporate notes/bonds
Financial assets:
Marketable securities:	57,480	56,436
Corporate notes/bonds \| Level 1
Financial assets:
Marketable securities:	$ 57,480	$ 56,436

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 and equity securities categorized neither as held-to-maturity nor trading.

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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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