Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Total income tax provision	$ 44.2	$ 55.0	$ 35.4
Effective tax rate	26.60%	27.50%	19.80%
Statutory federal tax rate	21.00%	21.00%	21.00%
Unrecognized tax benefits	$ 1.7	$ 1.9	$ 2.6
Accrued interest and penalties	0.3	$ 0.4
State and Local Jurisdiction [Member]
Valuation allowance	0.1
Domestic Tax Authority [Member]
Valuation allowance	$ 0.5

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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

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