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Benefit Plans - Pension Assets by Percentage (Details) - Pension Benefits | 12 Months Ended
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Dec. 25, 2021 | Dec. 26, 2020
Asset category [Abstract] |  |
Total plan assets (as a percent) | 100.00% | 100.00%
Expected long-term rate of return on plan assets | 4.96% | 4.69%
Equity securities (includes equity mutual funds) |  |
Asset category [Abstract] |  |
Total plan assets (as a percent) | 66.00% | 66.00%
Multi-asset securities |  |
Asset category [Abstract] |  |
Total plan assets (as a percent) | 24.00% | 24.00%
Cash and money market funds |  |
Asset category [Abstract] |  |
Total plan assets (as a percent) | 0.00% | 1.00%
Alternative investments |  |
Asset category [Abstract] |  |
Total plan assets (as a percent) | 10.00% | 9.00%
Maximum | Equity securities (includes equity mutual funds) |  |
Asset category [Abstract] |  |
Total plan assets (as a percent) | 70.00% |
Maximum | Alternative investments |  |
Asset category [Abstract] |  |
Total plan assets (as a percent) | 10.00% |

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- Definition Percentage of actual investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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