Income Taxes - Textual (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Income Tax Contingency [Line Items]
Provision for income tax expense	$ 34.3	$ 30.2	$ 88.6	$ 89.5
Net deferred tax assets	22.4		22.4
Valuation allowance	35.3		35.3
Gross unrecognized tax benefits	0.4		0.4		$ 0.9
Unrecognized tax benefits which would affect our effective tax rate if recognized	0.4		0.4		$ 0.9
Amount of decrease in unrecognized tax benefit to be released	0.3		0.3
State and Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Operating Loss Carryforwards	$ 61.4		$ 61.4

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

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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

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