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Income Taxes (Details 6) - USD ($) $ in Millions | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
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Income Tax Disclosure [Abstract] |  |  |  |
Deferred income taxes | $ 8.9 | $ 7.9 |  |
Other noncurrent liabilities | 11.2 | 11.7 |  |
Net unrecognized tax benefits | 20.1 | 19.6 |  |
Gross unrecognized tax benefits | $ 20.1 | $ 22.9 | $ 44.5 | $ 143.9

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- Definition Unrecognized Tax Benefit Recorded in Deferred Income Taxes + References No definition available. + Details
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