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Income Taxes (Narratives) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
U.S. federal statutory tax rate | 21.00% | 21.00% | 21.00%
Deferred Tax Assets, Operating Loss Carryforwards, Domestic | $ 0.0 |  |
Deferred Tax Assets, Operating Loss Carryforwards, Foreign | 1.3 |  |
Retained earnings | 1,174.4 | $ 926.3 |
Gross deferred tax assets | 71.7 | 79.6 |
Gross deferred tax liabilities | 160.4 | $ 188.1 |
Unrecognized Tax Benefits | 1.3 |  |
Deferred Tax Assets, Valuation Allowance, Operating Loss Carryforward |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Deferred Tax Assets, Valuation Allowance | 0.3 |  |
Foreign [Member] |  |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |  |
Retained earnings | $ 10.0 |  |

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