Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, compensation expense recognition, percentage of target	50.00%
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares that may be awarded (in shares)	1,196,000
Exercise period for shares awarded under 2007 Plan	10 years
Stock options may be awarded (in shares)	447,000
Outstanding share awards earned and issued at greater than the target number of shares	200.00%
Outstanding share awards earned and issued at greater than the target number of shares next fiscal year	150.00%
Stock-based compensation expense (benefit)	$ 469	$ 398
Total unrecognized compensation cost related to performance and restricted shares awarded	$ 349
Period of recognized compensation cost	1 year
2016 Plan \| Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period for performance shares awarded under 2007 Plan	3 years
2016 Plan \| Performance shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ultimate number of common shares that may be earned (in shares)	0
2016 Plan \| Performance shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares earned as percentage of initial target number shares awarded	200.00%
Common shares earned as percentage of initial target number shares awarded next fiscal year		150.00%
2016 Plan \| Restricted shares \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period	1 year
2016 Plan \| Restricted shares \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock vesting period	3 years

Common shares earned percentage of initial target number shares awarded.

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Common Shares Earned Percentage Of Initial Target Number Shares Awarded, Next Fiscal Year

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Common shares earned pursuant to award.

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Outstanding share awards earned and issued at greater than the target number of shares.

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Outstanding Share Awards Earned And Issued At Greater Than Target Number Of Shares, Next Fiscal Year

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Share-based Compensation Arrangement by Share-based Payment Award, Compensation Expense Recognition, Percentage Of Target

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Share-based Compensation Arrangement by Share-based Payment Award, Qualifying for the Award Period

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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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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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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