Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 1.3	$ 1.4	$ 2.9	$ 3.1
Tax benefit from compensation expense	0.3	$ 0.4	0.7	$ 0.8
Share-based compensation, compensation cost not yet recognized	$ 7.7		$ 7.7
Share-based compensation, compensation cost not yet recognized, recognition period			2 years 8 months 12 days
Restricted shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of vested stock awards			$ 1.4		$ 1.9