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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, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Mar. 31, 2022 | Mar. 31, 2021
Stock Compensation Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Equity based compensation expense |  | $ (22) | $ 316 | $ 315 | $ 471 |  |
Income tax benefit to equity based compensation |  | $ (6) | 73 | $ 69 | $ 111 |  |
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 |  | 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 |  |
Number of stock options | 33,000 |  |  |  |  |  |
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 | 53,000 |  |  |  |  |  |
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 awarded |  | 27,000 |  | 162,000 | 113,000 |  |
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 awarded |  | 18,000 |  |  |  |  | 54,000
Share-based compensation vesting percentage |  | 100.00% |  | 100.00% |  |  |
Vesting period |  | 3 years |  | 3 years |  |  |
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 awarded |  | 9,000 |  |  |  |  | 38,000
Share-based compensation vesting percentage |  | 33.33% |  | 33.33% |  |  |
Vesting period |  |  |  | 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 awarded |  |  |  |  |  |  | 21,000
Share-based compensation vesting percentage |  |  |  | 100.00% |  |  |
Vesting period |  |  |  | 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 awarded |  |  |  |  |  | 88,000 |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Scenario Forecast [Member] | Time Vested Restricted Stock [Member] | Officers and Key Employees [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Restricted stock awarded |  |  |  |  |  | 54,000 |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Scenario Forecast [Member] | Time Vested Restricted Stock [Member] | Director [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Restricted stock awarded |  |  |  |  |  | 20,000 |
Employee Stock Purchase Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Equity based compensation expense |  | $ (1) | 14 | $ 15 | $ 23 |  |
Income tax benefit to equity based compensation |  | $ 0 | $ 3 | $ 4 | $ 5 |  |
Maximum discount on purchase price of common stock percentage on fair market value |  | 15.00% |  |  |  |  |
Common stock may be purchased |  | 200 |  | 200 |  |  |

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