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Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Income Tax Disclosure [Abstract] |  |  |  |
Effective income tax rates | 19.20% | 27.30% | 17.90% | 42.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate |  |  | 21.00% |
Increase (Decrease) in Effective Tax Rate | (8.10%) |  | (24.10%) |
Changes to Liability for Uncertain Tax Positions |  |  | $ 0.0 |

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