Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Tax Disclosure [Abstract]
Effective tax rate (percent)	32.60%	33.90%	23.20%	33.00%
Unrecognized tax benefits	$ 12.4		$ 12.4
Unrecognized tax benefits that would decrease the effective tax rate if recognized	10.9		10.9
Unrecognized tax benefits that could be recognized within 12 months	3.6		3.6
Unrecognized tax benefits, penalties accrued	$ 0.7		$ 0.7

Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of unrecognized tax benefits.

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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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