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Pension and Other Benefit Programs (Summary of Fair Value Of Assets Plan) (Details) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | $ 395.4 | $ 378.5 |
Investments measured at net asset value per share as a practical expedient | 3.2 | 3.4 |
Net assets | 398.6 | 381.9 | $ 413.4
Collective trust funds - bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 357.6 | 342.3 |
Collective trust funds - equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 33.2 | 32.0 |
Cash equivalents, other short-term investments, receivables and payables [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 4.6 | 4.2 |
Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | (0.5) | (0.5) |
Level 1 [Member] | Collective trust funds - bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 0.0 | 0.0 |
Level 1 [Member] | Collective trust funds - equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 0.0 | 0.0 |
Level 1 [Member] | Cash equivalents, other short-term investments, receivables and payables [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | (0.5) | (0.5) |
Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 395.9 | 379.0 |
Level 2 [Member] | Collective trust funds - bonds |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 357.6 | 342.3 |
Level 2 [Member] | Collective trust funds - equities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | 33.2 | 32.0 |
Level 2 [Member] | Cash equivalents, other short-term investments, receivables and payables [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Cash equivalents, other short-term investments, receivables and payables, net | $ 5.1 | $ 4.7 |

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