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Share-Based Payments (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Restricted Stock Units (RSUs) [Member] |  |  |
Total unrecognized compensation cost related to unvested RSU awards | $ 10.6 |  |
Weighted average remaining expense life | 1 year 7 months 6 days |  |
Total intrinsic value of shares vested | $ 23.3 | $ 18.1 | $ 17.2
Dividend Equivalent Units [Member] |  |  |
Total intrinsic value of shares vested | $ 0.9 | 0.7 | 0.6
Cash Incentive Plan [Member] |  |  |
Weighted average remaining expense life | 9 months 18 days |  |
Share Based Compensation Liability Awards Amount Of Liability | $ 10.5 | 11.1 |
Cash incentive unit payments made | $ 3.0 | $ 2.9 | $ 2.2

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