Share-Based Compensation - Schedule of stock-based compensation costs (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2023 |
Mar. 31, 2022 |
Mar. 31, 2023 |
Mar. 31, 2022 |
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| Compensation Related Costs [Abstract] | ||||
| Share-based compensation costs | $ 4.5 | $ 5.5 | $ 9.1 | $ 10.8 |
| Less impact of income taxes | 1.0 | 1.2 | 2.1 | 2.5 |
| Share-based compensation costs, net of tax | $ 3.5 | $ 4.3 | $ 7.0 | $ 8.3 |
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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| X | ||||||||||
- Definition Amount, after tax, of expense for award under share-based payment arrangement. No definition available.
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- References No definition available.
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| X | ||||||||||
- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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