Stock-Based Compensation - Assumptions Used to Value Stock Options (Details) - $ / shares |
12 Months Ended | ||
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Sep. 30, 2022 |
Sep. 30, 2021 |
Sep. 30, 2020 |
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| Share-Based Payment Arrangement [Abstract] | |||
| Expected dividend yield | 0.00% | 0.00% | 0.00% |
| Risk-free interest rate, minimum | 0.40% | 0.40% | |
| Risk-free interest rate, maximum | 1.10% | 1.80% | |
| Volatility, minimum | 86.20% | 90.00% | |
| Volatility, maximum | 90.40% | 92.00% | |
| Expected term (in years) | 6 years 3 months | 6 years 3 months | |
| Weighted-average grant date fair value per share | $ 48.64 | $ 36.35 | |
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- References No definition available.
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. No definition available.
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- Definition The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. No definition available.
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. No definition available.
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. No definition available.
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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