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Retirement Benefits (Details 11) - Pension Benefits [Member] - USD ($) $ in Millions | Dec. 29, 2024 | Dec. 31, 2023 | Jan. 01, 2023
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 279.8 | $ 289.1 | $ 1,599.5
NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 85.8 | 166.9 |
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 194.0 | 122.2 |
Significant Observable Inputs (Level 2) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Significant Unobservable Inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Equity Securities: Other U.S. equities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.1 | 0.1 |
Equity Securities: Other U.S. equities [Member] | NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Equity Securities: Other U.S. equities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.1 | 0.1 |
Equity Securities: Other U.S. equities [Member] | Significant Observable Inputs (Level 2) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Equity Securities: Other U.S. equities [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Equity Securities: International equities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0.1 |
Equity Securities: International equities [Member] | NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0.0 |
Equity Securities: International equities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0.1 |
Equity Securities: International equities [Member] | Significant Observable Inputs (Level 2) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0.0 |
Equity Securities: International equities [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets |  | 0.0 |
Fixed income and cash equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 199.2 | 130.3 |
Fixed income and cash equivalents [Member] | NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 5.3 | 8.3 |
Fixed income and cash equivalents [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 193.9 | 122.0 |
Fixed income and cash equivalents [Member] | Significant Observable Inputs (Level 2) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Fixed income and cash equivalents [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Private equity [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 60.8 | 60.8 |
Private equity [Member] | NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 60.8 | 60.8 |
Private equity [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Private equity [Member] | Significant Observable Inputs (Level 2) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Private equity [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Alternative investments |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 19.7 | 97.8 |
Alternative investments | NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 19.7 | 97.8 |
Alternative investments | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Alternative investments | Significant Observable Inputs (Level 2) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | 0.0 | 0.0 |
Alternative investments | Significant Unobservable Inputs (Level 3) [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair value of plan assets | $ 0.0 | $ 0.0 |

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