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Benefit Plans - The Company's Pension Plan Assets Measured at Fair Value (Details) - USD ($) $ in Thousands | Jan. 01, 2022 | Dec. 26, 2020
--- | --- | ---
Defined Benefit Plan Disclosure |  |
Total pension plan assets | $ 48,325 | $ 100,478
Insurance contracts and other |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 2,260 | 2,565
Cash and cash equivalents |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 5,016 | 4,522
Equity securities |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 9,163 | 8,623
Fixed income |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 31,886 | 31,675
Bulk annuity contract |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets |  | 53,093
Level 1 |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 8,942 | 8,537
Level 1 | Insurance contracts and other |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
Level 1 | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 384 | 654
Level 1 | Equity securities |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 2,559 | 1,719
Level 1 | Fixed income |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 5,999 | 6,164
Level 1 | Bulk annuity contract |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets |  |
Level 2 |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 33,433 | 32,085
Level 2 | Insurance contracts and other |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 1,917 | 1,880
Level 2 | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 4,632 | 3,868
Level 2 | Equity securities |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 6,604 | 6,904
Level 2 | Fixed income |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 20,280 | 19,433
Level 2 | Bulk annuity contract |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets |  |
Level 3 |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 343 | 53,778
Level 3 | Insurance contracts and other |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 343 | 685
Level 3 | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
Level 3 | Equity securities |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
Level 3 | Fixed income |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
Level 3 | Bulk annuity contract |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets |  | 53,093
NAV |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 5,607 | 6,078
NAV | Insurance contracts and other |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
NAV | Cash and cash equivalents |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
NAV | Equity securities |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | 0 | 0
NAV | Fixed income |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets | $ 5,607 | 6,078
NAV | Bulk annuity contract |  |
Defined Benefit Plan Disclosure |  |
Total pension plan assets |  |

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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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