Income Taxes - Tax Cuts and Jobs Act (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Income Tax Disclosure [Abstract]
Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Deferred Tax Asset, Income Tax Expense (Benefit)	$ 46.6

Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Deferred Tax Asset, Income Tax Expense (Benefit)

No definition available.

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