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Marketable Securities - Schedule of Marketable Securities by Category (Details) - USD ($)
$ in Thousands
Sep. 25, 2021
Dec. 26, 2020
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost $ 309,326 $ 236,649
Gross Unrealized Holding Gains 133 372
Gross Unrealized Holding Losses 115 19
Fair Value 309,344 237,002
Municipal notes and bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 157,345 124,387
Gross Unrealized Holding Gains 100 257
Gross Unrealized Holding Losses 34 4
Fair Value 157,411 124,640
Asset-backed securities [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 3,230 11,679
Gross Unrealized Holding Gains 1 29
Gross Unrealized Holding Losses 0 0
Fair Value 3,231 11,708
Certificates of deposits [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 37,702 36,349
Gross Unrealized Holding Gains 12 24
Gross Unrealized Holding Losses 0 0
Fair Value 37,714 36,373
Commercial paper [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 66,716 32,690
Gross Unrealized Holding Gains 13 12
Gross Unrealized Holding Losses 1 3
Fair Value 66,728 32,699
Corporate bonds [Member]    
Schedule of Available-for-sale Securities [Line Items]    
Amortized Cost 44,333 31,544
Gross Unrealized Holding Gains 7 50
Gross Unrealized Holding Losses 80 12
Fair Value $ 44,260 $ 31,582