Share-Based Compensation - Schedule of stock-based compensation costs (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2019 |
Mar. 31, 2018 |
Mar. 31, 2019 |
Mar. 31, 2018 |
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| Compensation Related Costs [Abstract] | ||||
| Share-based compensation costs | $ 3.9 | $ 3.9 | $ 5.8 | $ 6.2 |
| Less impact of income tax benefit | 0.9 | 1.0 | 1.3 | 1.6 |
| Share-based compensation costs, net of tax | $ 3.0 | $ 2.9 | $ 4.5 | $ 4.6 |
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. No definition available.
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| X | ||||||||||
- References No definition available.
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- Definition The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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