Stock-based Compensation - Stock Options Outstanding (Details) - Stock options	6 Months Ended
Mar. 31, 2022 $ / shares shares
Shares
Outstanding at beginning of period (shares) \| shares	114,259
Granted (shares) \| shares	236
Exercised (shares) \| shares	(788)
Expired (shares) \| shares	(86,000)
Outstanding at end of period (shares) \| shares	27,707
Exercisable at end of period (shares) \| shares	27,471
Weighted Average Exercise Price
Outstanding at beginning of period (in USD per share) \| $ / shares	$ 17.89
Granted (in USD per share) \| $ / shares	16.58
Exercised (in USD per share) \| $ / shares	12.32
Expired (in USD per share) \| $ / shares	19.11
Outstanding at end of period (in USD per share) \| $ / shares	14.26
Exercisable at end of period (in USD per share) \| $ / shares	$ 14.24

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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

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No definition available.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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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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No definition available.

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

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