Investments - Summary of Available for Sale Investments (Details) - USD ($) $ in Thousands	Apr. 03, 2020	Sep. 27, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 102,142	$ 101,224
Gross Unrealized Holding Gains	28	113
Gross Unrealized Holding Losses	(1,323)	(111)
Aggregate Fair Value	100,847	101,226
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	29,778	29,578
Gross Unrealized Holding Gains	0	112
Gross Unrealized Holding Losses	(1,291)	(93)
Aggregate Fair Value	28,487	29,597
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	72,364	71,646
Gross Unrealized Holding Gains	28	1
Gross Unrealized Holding Losses	(32)	(18)
Aggregate Fair Value	$ 72,360	$ 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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