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Income Taxes (Narratives) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
U.S. federal statutory tax rate | 21000000.00% | 21000000.00% | 21000000.00%
Deferred Tax Assets, Operating Loss Carryforwards, Domestic | $ 0.2 |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | 1.5 |  |
Retained earnings | 1,195.6 | $ 1,200.0 |
Gross deferred tax assets | 61.0 | 59.3 |
Gross deferred tax liabilities | 216.4 | 187.6 |
Unrecognized Tax Benefits | 1.2 | $ 1.4 |
Deferred Tax Assets, Valuation Allowance, Operating Loss Carryforward |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Deferred Tax Assets, Valuation Allowance | 0.6 |  |
Foreign [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Retained earnings | $ 25.1 |  |

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