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Retirement Benefits - Narrative (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
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Oct. 01, 2023 USD ($) | Dec. 28, 2025 | Dec. 29, 2024 USD ($) employee uSRetireeAndBeneficiary | Dec. 31, 2023 USD ($) | Jan. 01, 2023 USD ($) | Jan. 02, 2022 | Jan. 03, 2021 | Oct. 17, 2023 uSRetireeAndBeneficiary
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Projected Retirement Benefit Expense In Next 12 months |  |  | $ 22.0 |  |  |  |  |
Defined Contribution Plan, Cost |  |  | 42.5 | $ 38.8 | $ 31.1 |  |  |
Income tax provision (benefit) |  |  | 103.4 | (128.2) | 15.5 |  |  |
Settlement loss (gain) included in net income (loss) |  |  | $ 0.0 | 1.1 | 0.7 |  |  |
Transfer Of Defined Benefit Pension Plan, Percentage |  |  |  |  |  |  |  | 85.00%
Number Of U.S. Retirees And Beneficiaries Transferred | uSRetireeAndBeneficiary |  |  |  |  |  |  |  | 8,200
Number Of U.S. Retirees And Beneficiaries | uSRetireeAndBeneficiary |  |  | 2,000 |  |  |  |  |
Reclassification out of Accumulated Other Comprehensive Income [Member] | Post- retirement benefit plans [Member] |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Income tax provision (benefit) |  |  | $ (1.1) | (1.4) | (2.8) |  |  |
Settlement loss (gain) included in net income (loss) |  |  | 0.0 | 1.1 | 0.7 |  |  |
Other Postretirement Benefits |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Employer contributions |  |  | 0.0 | 0.0 |  |  |  |
Projected Retirement Benefit Expense In Next 12 months |  |  | 15.0 |  |  |  |  |
Defined Contribution Plan, Cost |  |  | $ 1.0 | $ 1.0 | $ 1.0 |  |  |
Assumed increase in per capita cost of covered benefits in next 12 months |  |  | 6.60% |  |  |  |  |
Assumed ultimate health care cost trend rate |  |  | 4.00% |  |  |  |  |
Expected long-term rate of return on assets |  |  | 0.00% | 0.00% | 0.00% |  |  |
Fair value of plan assets |  |  | $ 0.0 | $ 0.0 | $ 0.0 |  |  |
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement |  |  | 0.0 | 0.0 |  |  |  |
Settlement loss (gain) included in net income (loss) |  |  | 0.0 | 0.0 |  |  |  |
Pension Benefits [Member] |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Employer contributions | $ 222.0 |  | 3.3 | 278.0 |  |  |  |
Projected Retirement Benefit Expense In Next 12 months |  |  | 7.0 |  |  |  |  |
Accumulated benefit obligation |  |  | $ 292.3 | $ 281.3 |  |  |  |
Expected long-term rate of return on assets |  |  | 5.80% |  | 6.43% |  |  |
Actual return on plan assets |  |  | (2.70%) | 2.00% | (14.50%) | 12.40% | 15.20% |
Fair value of plan assets |  |  | $ 279.8 | $ 289.1 | $ 1,599.5 |  |  |
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement |  |  | 0.0 | 1,350.6 |  |  |  |
Settlement loss (gain) included in net income (loss) |  |  | 0.0 | 1.1 |  |  |  |
Pension Benefits [Member] | Private equity [Member] |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Unfunded commitments |  |  | 37.0 |  |  |  |  |
Fair value of plan assets |  |  | 60.8 | 60.8 |  |  |  |
Pension Benefits [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Fair value of plan assets |  |  | 0.0 | 0.0 |  |  |  |
Pension Benefits [Member] | Fair Value, Inputs, Level 3 [Member] | Private equity [Member] |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Fair value of plan assets |  |  | $ 0.0 | 0.0 |  |  |  |
Pension Benefits [Member] | Forecast |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Expected long-term rate of return on assets |  | 5.80% |  |  |  |  |  |
Pension Benefits [Member] | United States |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Defined benefit plan, number of employees accruing benefit service | employee |  |  | 800 |  |  |  |  |
Percent reduction in defined benefit plan participation |  |  |  |  | 60.00% |  |  |
Employer contributions |  |  | $ 0.0 | $ 272.0 | $ 50.0 |  |  |
Nonqualified plans |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |
Estimated employer contributions in next 12 months |  |  | $ 5.0 |  |  |  |  |

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