Short-Term Investments (Details) - USD ($) $ in Thousands	Oct. 02, 2021	Oct. 03, 2020	Sep. 28, 2019
Debt Securities, Available-for-sale [Abstract]
Cash and cash equivalents: cost basis	$ 456,534	$ 440,258
Cash Equivalent, Unrealized Gains	0	0
Cash Equivalent, Unrealized Losses	0	0
Cash and cash equivalents	456,534	440,258	$ 305,833
Available-for-sale securities, fair value	$ 0	35,346
U.S. Treasury and agency obligations
Debt Securities, Available-for-sale [Abstract]
Available-for-sale securities: cost basis		35,311
Available-for-sale securities: unrealized gains		36
Available-for-sale securities: unrealized losses		(1)
Available-for-sale securities, fair value		35,346
U.S. Treasury and agency obligations \| Short-term investments
Debt Securities, Available-for-sale [Abstract]
Available-for-sale securities: cost basis		35,311
Available-for-sale securities: unrealized gains		36
Available-for-sale securities: unrealized losses		(1)
Debt securities, available-for-sale		$ 35,346

Cash, Cash Equivalent and Restricted Cash, Cost Basis

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Cash Equivalent, Unrealized Gains

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Cash Equivalent, Unrealized Losses

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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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Amortized cost 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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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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Amount 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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