Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Taxes [Abstract]
Income Tax Expense (Benefit)	$ 12.4	$ 5.3	$ 34.6	$ 19.0
Effective Income Tax Rate Reconciliation, Percent	25.00%		27.00%	25.00%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate			21.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent			1.70%	1.20%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent			2.00%	1.40%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent			1.00%	1.30%

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 applicable to statutory income tax expense (benefit) outside of the country of domicile.

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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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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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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