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Fair Value Measurements - Summary of Assets at Fair Value on a Recurring Basis (Details) - Recurring - USD ($) $ in Thousands | Jul. 11, 2021 | Dec. 27, 2020
--- | --- | ---
Assets: |  |
Investments in rabbi trust | $ 6,113 | $ 6,740
Total assets measured at fair value | 6,113 | 6,740
Level 1 |  |
Assets: |  |
Investments in rabbi trust | 6,113 | 6,740
Total assets measured at fair value | 6,113 | 6,740
Level 2 |  |
Assets: |  |
Investments in rabbi trust | 0 | 0
Total assets measured at fair value | 0 | 0
Level 3 |  |
Assets: |  |
Investments in rabbi trust | 0 | 0
Total assets measured at fair value | $ 0 | $ 0

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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