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Equity-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Aug. 11, 2020 | Sep. 30, 2022 | Jun. 30, 2022 | Sep. 30, 2021 | Jun. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021 | Mar. 31, 2023 | Mar. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  |  |  | 223,000 |  |  |
Stock Compensation Plan [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Equity based compensation expense |  | $ 201 |  | $ 22 |  | $ 306 | $ 315 |  |
Income tax benefit to equity based compensation |  | $ 44 |  | $ (6) |  | $ 67 | $ 69 |  |
Amended and Restated 2000 Incentive Plan [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  | 9,000 |  |  |  |  |
Share-based compensation vesting percentage |  |  |  | 33.00% |  |  |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Stock Compensation Plan [Member] | Maximum |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Number of shares authorized |  | 422,000 |  |  |  | 422,000 |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Stock Compensation Prior Plan [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Remaining available shares under equity based compensation plan |  |  |  |  |  |  |  |  | 112,000
Amended and Restated 2000 Incentive Plan [Member] | Employee Stock Option [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Stock option awards granted | 0 | 0 |  | 0 |  | 0 | 0 |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Number of unvested restricted stock | 13,000 |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  | 27,000 |  |  | 162,000 |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Performance Vested Restricted Stock [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  | 0 |  |  |  | 0 |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Performance Vested Restricted Stock [Member] | Officer [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  | 18,000 |  | 112,000 |  |  |
Share-based compensation vesting percentage |  |  |  | 100.00% |  | 100.00% |  |  |
Vesting period |  |  |  |  |  | 3 years |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Performance Vested Restricted Stock [Member] | Officers and Key Employees [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  | 54,000 |  |  |  |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Performance Vested Restricted Stock [Member] | Director [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  | 20,000 |  |  |  |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Time Vested Restricted Stock [Member] | Officer [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  |  |  | 18,000 |  |  |
Share-based compensation vesting percentage |  |  |  |  |  | 100.00% |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Time Vested Restricted Stock [Member] | Officers and Key Employees [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  |  |  | 56,000 |  |  |
Share-based compensation vesting percentage |  |  |  |  | 33.33% | 33.33% |  |  |
Vesting period |  |  |  |  | 3 years | 3 years |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Time Vested Restricted Stock [Member] | Director [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  |  |  | 37,000 |  |  |
Share-based compensation vesting percentage |  |  | 100.00% |  |  | 100.00% |  |  |
Vesting period |  |  | 1 year |  |  | 1 year |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Scenario Forecast [Member] | Performance Vested Restricted Stock [Member] | Officer [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Restricted Stock, Granted |  |  |  |  |  |  |  | 88,000 |
Share-based compensation vesting percentage |  |  |  |  |  |  |  | 100.00% |
Employee Stock Purchase Plan [Member] |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |
Equity based compensation expense |  | $ (3) |  | $ (1) |  | $ 6 | $ 15 |  |
Income tax benefit to equity based compensation |  | $ (1) |  | $ (1) |  | $ 1 | $ 4 |  |
Maximum discount on purchase price of common stock percentage on fair market value |  |  |  |  |  | 15.00% |  |  |
Common stock may be purchased |  |  | 400 |  |  |  |  |  |

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