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Marketable Securities - Summary of Estimated Fair Value and Gross Unrealized Holding Losses of Marketable Securities in Unrealized Loss Position (Details) - USD ($)
$ in Thousands
Jun. 26, 2021
Dec. 26, 2020
Schedule of Available-for-sale Securities [Line Items]    
In Unrealized Loss Position For Less Than 12 Months, Fair Value $ 59,714 $ 32,450
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses 81 19
In Unrealized Loss Position For Greater Than 12 Months, Fair Value 0 0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses 0 0
Municipal notes and bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
In Unrealized Loss Position For Less Than 12 Months, Fair Value 30,626 8,641
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses 19 4
In Unrealized Loss Position For Greater Than 12 Months, Fair Value 0 0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses 0 0
Certificates of deposits [Member]    
Schedule of Available-for-sale Securities [Line Items]    
In Unrealized Loss Position For Less Than 12 Months, Fair Value 4,603  
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses 1  
In Unrealized Loss Position For Greater Than 12 Months, Fair Value 0  
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses 0  
Commercial paper [Member]    
Schedule of Available-for-sale Securities [Line Items]    
In Unrealized Loss Position For Less Than 12 Months, Fair Value   8,862
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses   3
In Unrealized Loss Position For Greater Than 12 Months, Fair Value   0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses   0
Corporate bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
In Unrealized Loss Position For Less Than 12 Months, Fair Value 24,485 14,947
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses 61 12
In Unrealized Loss Position For Greater Than 12 Months, Fair Value 0 0
In Unrealized Loss Position For Greater Than 12 Months, Gross Unrealized Losses $ 0 $ 0