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Marketable Securities - Schedule of Marketable Securities Classified as Available-for-sale Securities (Details) - USD ($)
$ in Thousands
Jun. 26, 2021
Dec. 26, 2020
Marketable Securities [Line Items]    
Amortized Cost $ 1,519,722 $ 1,492,770
Gross Unrealized Gains 22,142 30,886
Gross Unrealized Losses (7,592) (4,839)
Fair Value 1,534,272 1,518,817
U.S. Treasury securities [Member] | Fair Value, Level 2 [Member]    
Marketable Securities [Line Items]    
Amortized Cost 400 400
Gross Unrealized Gains 3 6
Fair Value 403 406
Agency securities [Member] | Fair Value, Level 2 [Member]    
Marketable Securities [Line Items]    
Amortized Cost 8,474 5,954
Gross Unrealized Gains 12 56
Gross Unrealized Losses (29)  
Fair Value 8,457 6,010
Mortgage-backed securities [Member] | Fair Value, Level 2 [Member]    
Marketable Securities [Line Items]    
Amortized Cost 173,372 239,445
Gross Unrealized Gains 818 1,051
Gross Unrealized Losses (789) (1,923)
Fair Value 173,401 238,573
Corporate securities [Member] | Fair Value, Level 2 [Member]    
Marketable Securities [Line Items]    
Amortized Cost 997,362 984,696
Gross Unrealized Gains 18,346 25,962
Gross Unrealized Losses (4,294) (1,637)
Fair Value 1,011,414 1,009,021
Municipal securities [Member] | Fair Value, Level 2 [Member]    
Marketable Securities [Line Items]    
Amortized Cost 301,919 214,515
Gross Unrealized Gains 2,872 3,644
Gross Unrealized Losses (1,950) (223)
Fair Value 302,841 217,936
Other [Member] | Fair Value, Level 2 [Member]    
Marketable Securities [Line Items]    
Amortized Cost 38,195 47,760
Gross Unrealized Gains 91 167
Gross Unrealized Losses (530) (1,056)
Fair Value $ 37,756 $ 46,871