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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2015 | Sep. 30, 2014 | Jun. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Jul. 17, 2013
Income Tax Contingency [Line Items] |  |  |  |  |  |
Effective tax rates (as a percent) |  | 13.00% |  |  | 31.00% |
U.S. statutory rate (as a percent) |  |  | 35.00% | 35.00% |  |
Income Tax Expense (Benefit) | $ (1.6) | $ (4.7) |  | $ 0.8 | $ 11.4 |
Tax Assessment Year 2007 to 2009 | Internal Revenue Service (IRS) |  |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |  |
Total tax assessment |  |  |  |  |  | $ 4.0
Tax assessments related to disallowed deductions |  |  |  |  |  | $ 2.7

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