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Equity-Based Compensation - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Jun. 30, 2020 | Jun. 30, 2019
Stock Compensation Plan [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Equity based compensation expense | $ 155 | $ 87
Income tax benefit to equity based compensation | $ 38 | $ 20
Employee Stock Option [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Stock options maximum term | 10 years |
Amended and Restated 2000 Incentive Plan [Member] | Stock Compensation Plan [Member] | Maximum [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares authorized | 1,375,000 |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Restricted stock awarded | 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 |
Amended and Restated 2000 Incentive Plan [Member] | Restricted Stock [Member] | Maximum [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Number of shares authorized | 467,000 |
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
Employee Stock Purchase Plan [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Equity based compensation expense | $ 9 | $ 0
Income tax benefit to equity based compensation | $ 2 | $ 0
Maximum discount on purchase price of common stock percentage on fair market value | 15.00% |
Common stock may be purchased | 200 |

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