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Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Income Tax Disclosure [Abstract] |  |  |  |
Effective income tax rates | 26.40% | 28.20% | 35.30% | 35.80%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate |  |  | 35.00% |
Increase (Decrease) in Effective Tax Rate | (1.80%) |  | (0.50%) |
Changes to Liability for Uncertain Tax Positions |  |  | $ 0.0 |

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