Selected Quarterly Financial Information (unaudited) (Textuals) (Details) $ in Millions	3 Months Ended
Dec. 31, 2017 USD ($)
Quarterly Financial Information Disclosure [Abstract]
One-time charge to revalue deferred tax assets and liabilities	$ 31.8

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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