Investments - Summary of Available for Sale Investments - USD ($) $ in Thousands	Jul. 03, 2020	Sep. 27, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 132,846	$ 101,224
Gross Unrealized Holding Gains	601	113
Gross Unrealized Holding Losses	(199)	(111)
Aggregate Fair Value	133,248	101,226
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	30,097	29,578
Gross Unrealized Holding Gains	354	112
Gross Unrealized Holding Losses	(179)	(93)
Aggregate Fair Value	30,272	29,597
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	102,749	71,646
Gross Unrealized Holding Gains	247	1
Gross Unrealized Holding Losses	(20)	(18)
Aggregate Fair Value	$ 102,976	$ 71,629

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).

+ References

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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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