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Stock-based Compensation - Additional Information (Detail) - USD ($) |  | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 10, 2013 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2016 | Sep. 09, 2022 | Jun. 30, 2022 | Dec. 10, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares paid under ESOP |  | 353,222 |  |  |  | 353,222 |
Employee Stock Ownership Plan Esop [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Minimum hours of service required |  | 1000 hours |  |  |  |  |
Period of service to qualify for ESOP benefits |  | 12 months |  |  |  |  |
Minimum age of employee to attain the plan |  | 21 days |  |  |  |  |
Shares to be purchased for ESOP, from borrowed funds |  | 384,900 |  |  |  |  |
Shares to be purchased for ESOP, percentage of common stock |  | 8.00% |  |  |  |  |
Repayment of loan on ESOP |  | 20 years |  |  |  |  |
Percentage vested in accrued benefits |  | 100.00% |  |  |  |  |
Vesting period |  | 6 years |  |  |  |  |
Employee Stock Ownership Plan Esop [Member] | Employee Severance [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of shares paid under ESOP |  | 0 | 0 |  |  |  |
Employee Stock Ownership Plan Esop [Member] | Minimum [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Prorated vesting period |  | 2 years |  |  |  |  |
Employee Stock Ownership Plan Esop [Member] | Maximum [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Prorated vesting period |  | 5 years |  |  |  |  |
Equity Incentive Plan [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares authorized |  | 673,575 |  |  |  |  |
Equity Incentive Plan [Member] | Employee Stock Option [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period | 7 years |  |  |  |  |  |
Shares authorized | 167,000 | 481,125 |  |  |  |  |
Restricted stock available for future grants |  | 314,125 |  |  |  |  |
Stock options granted |  | 0 |  |  |  |  |
Options vested during the period |  | 0 |  |  |  |  |
Weighted average recognition period for non-vested restricted stock awards |  | 7 years |  |  |  |  |
Unrecognized compensation expense for non-vested restricted stock awards |  | $ 0 |  |  |  |  |
Equity Incentive Plan [Member] | Restricted Stock And Restricted Stock Units Rsu [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares authorized |  | 192,450 |  |  |  |  |
Equity Incentive Plan [Member] | Restricted Stock [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Vesting period | 10 years |  |  | 8 years |  |  |
Shares authorized | 85,500 |  |  |  | 53,000 |  | 16,900
Restricted stock available for future grants |  | 38,800 |  |  |  |  |
Weighted average recognition period for non-vested restricted stock awards |  | 4 years 10 months 24 days |  |  |  |  |
Unrecognized compensation expense for non-vested restricted stock awards |  | $ 1,175,000 |  |  |  |  |
Stock based compensation expense |  | 56,000 | $ 42,000 |  |  |  |
Tax benefit |  | $ 16,000 | $ 12,000 |  |  |  |

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