Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Effective income tax	24.90%	20.80%	24.10%	21.90%
Deferred tax assets, net	$ 224.1		$ 224.1		$ 275.6
Gross unrecognized tax benefits	22.4		22.4		30.6
Accrued interest and penalties on unrecognized tax benefits	6.0		6.0		$ 5.8
Possible decrease in unrecognized tax benefits	$ 8.4		$ 8.4

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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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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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

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Amount of unrecognized tax benefits.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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