Equity-Based Compensation - Stock Option Activity (Details) - $ / shares	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Stock Options
Outstanding at beginning of period (shares)	5,210,566
Granted (shares)	3,179,472
Exercised (shares)	(548,277)
Forfeited (shares)	(294,139)
Outstanding at end of period (shares)	7,547,622	5,210,566
Weighted Average Exercise Price
Outstanding at beginning of period, weighted average exercise price (in USD per share)	$ 25.26	$ 21.73
Granted, weighted average exercise price (in USD per share)	29.88
Exercised, weighted average exercise price (in USD per share)	17.04
Forfeited, weighted average exercise price (in USD per share)	28.00
Outstanding at end of period, weighted average exercise price (in USD per share)	$ 25.26	$ 21.73

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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