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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2017 | Mar. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Tax expense (benefit) | $ 2.2 | $ 6.9
Effective tax rate | 3.60% | 24.80%
Accounting Standards Update 2016-09 [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Tax expense (benefit) | $ (15.9) |

X
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