Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Income Tax Expense (Benefit)	$ 5.4	$ 6.2
Effective Income Tax Rate Reconciliation, Percent	25.00%	25.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	21.00%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	2.00%	2.00%
Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Percent	3.00%	0.10%

Income Taxes [Abstract]

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments.

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to excess tax benefit for share-based compensation cost.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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