Marketable Securities - Schedule of Amortized Cost and Estimated Fair Value of Marketable Securities Classified by Maturity Date (Details) - USD ($) $ in Thousands	Dec. 26, 2020	Dec. 31, 2019
Available For Sale Securities Debt Maturities Fair Value [Abstract]
Amortized Cost, Due within one year	$ 170,099	$ 152,649
Amortized Cost, Due after one through five years	66,550	36,660
Amortized Cost, Due after five through ten years	0	0
Amortized Cost, Due after ten years	0	0
Amortized Cost	236,649	189,309
Fair Value, Due within one year	170,321	152,852
Fair Value, Due after one through five years	66,681	36,711
Fair Value, Due after five through ten years	0	0
Fair Value, Due after ten years	0	0
Fair Value, Total marketable securities	$ 237,002	$ 189,563

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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