Cash, Cash Equivalents, and Investments - Summary of Available-for-Sale Investments (Details) $ in Thousands	Sep. 27, 2020 USD ($)
Debt Securities, Available-for-sale [Line Items]
Amortized cost	$ 708,599
Gross unrealized gains	6,261
Gross unrealized losses	(152)
Fair value	714,708
Agency Bonds
Debt Securities, Available-for-sale [Line Items]
Fair value	28,274
Agency Bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	28,193
Gross unrealized gains	81
Gross unrealized losses	0
Fair value	28,274
Treasury Bills
Debt Securities, Available-for-sale [Line Items]
Fair value	270,091
Treasury Bills \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	268,071
Gross unrealized gains	2,030
Gross unrealized losses	(10)
Fair value	270,091
Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Fair value	259,887
Corporate Bonds \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	43,208
Gross unrealized gains	254
Gross unrealized losses	(26)
Fair value	43,436
Corporate Bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	213,850
Gross unrealized gains	2,717
Gross unrealized losses	(116)
Fair value	216,451
Asset-Backed Securities
Debt Securities, Available-for-sale [Line Items]
Fair value	129,543
Asset-Backed Securities \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	34,277
Gross unrealized gains	259
Gross unrealized losses	0
Fair value	34,536
Asset-Backed Securities \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	94,270
Gross unrealized gains	737
Gross unrealized losses	0
Fair value	95,007
Sovereign Bonds
Debt Securities, Available-for-sale [Line Items]
Fair value	24,496
Sovereign Bonds \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	15,978
Gross unrealized gains	108
Gross unrealized losses	0
Fair value	16,086
Sovereign Bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	8,349
Gross unrealized gains	61
Gross unrealized losses	0
Fair value	8,410
Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Fair value	2,417
Municipal Bonds \| Short-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	1,298
Gross unrealized gains	9
Gross unrealized losses	0
Fair value	1,307
Municipal Bonds \| Long-Term Investments
Debt Securities, Available-for-sale [Line Items]
Amortized cost	1,105
Gross unrealized gains	5
Gross unrealized losses	0
Fair value	$ 1,110

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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