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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 | Mar. 27, 2021 | Dec. 26, 2020
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Schedule of Available-for-sale Securities [Line Items] |  |
In Unrealized Loss Position For Less Than 12 Months, Fair Value | $ 42,040 | $ 32,450
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses | 50 | 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 | 15,472 | 8,641
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses | 9 | 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
Commercial paper [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In Unrealized Loss Position For Less Than 12 Months, Fair Value | 5,991 | 8,862
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses | 1 | 3
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
Corporate bonds [Member] |  |
Schedule of Available-for-sale Securities [Line Items] |  |
In Unrealized Loss Position For Less Than 12 Months, Fair Value | 20,577 | 14,947
In Unrealized Loss Position For Less Than 12 Months, Gross Unrealized Losses | 40 | 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

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121590138&loc=SL82922954-210456 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922890-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27337-111563 + Details
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