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Benefit Plans - Pension Assets by Percentage (Details) - Pension Benefits | Dec. 31, 2022 | Dec. 25, 2021
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Asset category |  |
Total plan assets (as a percent) | 100.00% | 100.00%
Equity securities (includes equity mutual funds) |  |
Asset category |  |
Total plan assets (as a percent) | 67.00% | 66.00%
Multi-asset securities |  |
Asset category |  |
Total plan assets (as a percent) | 22.00% | 24.00%
Cash and equivalents (includes money market funds) |  |
Asset category |  |
Total plan assets (as a percent) | 1.00% | 0.00%
Alternative investments |  |
Asset category |  |
Total plan assets (as a percent) | 10.00% | 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 https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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