Share-Based Compensation - Schedule of stock-based compensation costs (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
Mar. 31, 2018 |
Mar. 31, 2017 |
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| Compensation Related Costs [Abstract] | ||||
| Share-based compensation costs | $ 3.9 | $ 3.1 | $ 6.2 | $ 5.7 |
| Less impact of income tax benefit | 1.0 | 1.0 | 1.6 | 2.0 |
| Share-based compensation costs, net of tax | $ 2.9 | $ 2.1 | $ 4.6 | $ 3.7 |
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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://www.xbrl.org/2003/role/presentationRef
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- 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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- 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://www.xbrl.org/2003/role/presentationRef
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