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Equity-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Aug. 11, 2020 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Stock Compensation Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Equity based compensation expense |  | $ 316 | $ 313 | $ 471 | $ 401
Income tax benefit to equity based compensation |  | $ 73 | $ 69 | $ 111 | $ 89
Employee Stock Option [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock option awards granted |  | 0 | 0 | 0 | 0
Stock options maximum term |  |  |  | 10 years |
2020 Equity Incentive Plan [Member] | Stock Compensation Plan [Member] |  |  |  |  |
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 |  |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Restricted stock awarded |  | 0 | 0 | 113,000 | 83,000
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 |  |  |  | 54,000 | 40,000
Share-based compensation vesting percentage |  |  |  | 100.00% |
Vesting period |  |  |  | 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 |  |  |  | 38,000 | 28,000
Share-based compensation vesting percentage |  |  |  | 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 | 15,000
Share-based compensation vesting percentage |  |  |  | 100.00% |
Vesting period |  |  |  | 1 year |
Employee Stock Purchase Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Equity based compensation expense |  | $ 14 | $ 11 | $ 23 | $ 11
Income tax benefit to equity based compensation |  | $ 3 | $ 2 | $ 5 | $ 2
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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- Definition Maximum discount rate from fair value of market price on the last, first or lower of the last or first day of the offering period that participants pay for shares. + References No definition available. + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the 2000 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. + References No definition available. + Details
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