Recent Accounting Pronouncements and U.S. Tax Reform (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
Jun. 30, 2018	Sep. 30, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease obligations	$ 3.7
Average discount rate, remaining rental payments	4.00%
Tax benefit, Tax Cuts and Jobs Act	$ 0.5
Minimum [Member] \| Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative adjustment for adoption of accounting standard	2.0
Maximum [Member] \| Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cumulative adjustment for adoption of accounting standard	$ 3.0
Scenario, Forecast [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
U.S. Statutory Federal Rate		25.00%

Tax Cuts and Jobs Act of 2017, Incomplete Accounting, AMT Tax Credit, Income Tax Expense (Benefit)

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