Commitments and Contingencies - Income Taxes (Details) $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Provisional estimate	$ 0.4

Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Change In Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense

No definition available.

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