Equity-Based Compensation - Summary of the Company Restricted Stock Award Activity (Details) - $ / shares	6 Months Ended
Mar. 31, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-Avg Purchase Price per Share, Beginning Balance	$ 19.05	$ 21.55
Granted, weighted average exercise price	15.04
Exercised, Weighted Average Exercise Price	13.49
Forfeited, weighted average exercise price	17.55
Weighted Average Exercise Price, Outstanding at March 31, 2022	$ 19.05
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Outstanding \| shares	802,000
Granted \| shares	0
Exercised \| shares	229,000,000,000
Forfeited \| shares	23,000,000,000
Ending balance, Outstanding \| shares	550,000,000,000
Weighted-Avg Purchase Price per Share, Beginning Balance	$ 14.40	$ 14.31
Granted, weighted average exercise price	0
Exercised, Weighted Average Exercise Price	14.08
Forfeited, weighted average exercise price	14.39
Weighted Average Exercise Price, Outstanding at March 31, 2022	$ 14.40

Share based compensation arrangement by share based payment award redeemed units in period.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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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