Income Taxes - Impact of Tax Cuts and Jobs Act (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal Taxes on Mandatory Deemed Repatriation	$ (16.8)	$ 150.0
Impact Related to Federal Deferred Taxes	12.7	(210.0)
Other Adjustments	(0.7)	6.9
Provision (Benefit) for Income Taxes	$ (4.8)	$ (53.1)	$ 0.0

Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Income Tax Expense (Benefit)

No definition available.

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