Income Taxes (Additional Information) (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Income Tax Disclosure [Abstract]
Estimated income tax expense (benefit), discrete items	$ (24.4)
Estimated reduction in deferred income tax liabilities	30.8
Estimated increase in income tax payable due to transition tax	$ 6.5

Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefits)

No definition available.

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