Equity-Based Compensation - Summary of Company's Restricted Stock Award Activity (Details)	9 Months Ended
Jun. 30, 2022 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted Average Exercise Price, Outstanding at September 30, 2021	$ 21.55
Granted, weighted average exercise price	15.04
Exercised, Weighted Average Exercise Price	13.49
Forfeited, weighted average exercise price	18.09
Weighted Average Exercise Price, Outstanding at June 30, 2022	$ 19.06
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Outstanding \| shares \| shares	802,000
Granted \| shares \| shares	0
Exercised \| shares \| shares	235,000
Forfeited \| shares \| shares	23,000
Ending balance, Outstanding \| shares \| shares	544,000
Weighted Average Exercise Price, Outstanding at September 30, 2021	$ 14.31
Granted, weighted average exercise price	0
Exercised, Weighted Average Exercise Price	14.10
Forfeited, weighted average exercise price	14.39
Weighted Average Exercise Price, Outstanding at June 30, 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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).

+ References

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

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

+ References

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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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- Definition

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

+ References

No definition available.

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