Income Taxes (Narrative) (Detail) - 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 Contingency [Line Items]
Company's effective tax rate	23.20%	23.10%	22.20%	21.10%
Unrecognized Tax Benefits, Period Increase (Decrease)	$ 0.4		$ 1.7
Increase In unrecognized tax benefits that would impact effective tax rate	0.8		2.4
Recognized interest expense related to unrecognized tax benefits	0.6		1.2
Interest and penalty related to unrecognized tax benefits recorded	8.4		8.4		$ 7.2
Reasonable possible increase in unrecognized tax benefits during the next twelve months	$ 9.6		$ 9.6

Increase In Unrecognized Tax Benefits That Would Impact Effective Tax Rate.

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- Definition

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

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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.

+ References

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Amount of interest expense accrued for an underpayment of income taxes.

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Amount of interest expense for an underpayment of income taxes.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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