Equity Compensation Plans - Stock Options (Details) - Stock Options - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Equity Compensation Plans
Award vesting period	3 years
Contractual term	10 years
Compensation expenses	$ 0	$ 0
Number of Options
Outstanding, beginning of period (in shares)	227,406
Outstanding, end of period (in shares)	227,406	227,406
Weighted-Average Exercise Price Per Share
Outstanding, beginning of period (in dollars per share)	$ 9.50
Outstanding, end of period (in dollars per share)	$ 9.50	$ 9.50
Aggregate Intrinsic Value
Aggregate intrinsic value, outstanding	$ 2,298	$ 2,043
Weighted Average Remaining Contractual Term
Weighted-average remaining contractual term, outstanding	2 years 5 months 12 days	3 years 6 months 3 days

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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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 remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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