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Stock Compensation Plans - Additional Information (Detail) - USD ($) |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Aug. 11, 2020 | Sep. 30, 2022 | Mar. 31, 2023 | Mar. 31, 2022 | Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock based compensation expense |  |  | $ 785,000 | $ 780,000 | $ 817,000
Income tax benefit to stock based compensation |  |  | $ 173,000 | $ 173,000 | $ 193,000
Maximum discount on purchase price of common stock percentage on fair market value |  | 15.00% |  |  |
Common stock may be purchased |  |  | 4 |  |
Performance Vested Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock option awards granted |  |  |  | 88,000 | 54,000
Time Vested Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock option awards granted |  |  |  | 76,000 | 59,000
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Unrecognized stock-based compensation expense |  |  | $ 2,345,000 |  |
Weighted average period for recognize expense |  |  | 1 year 9 months 3 days |  |
2020 Equity Incentive Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Awards available for future grants |  |  | 256,000 |  |
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 |  |  |  |
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 |  |  |  |
Amended and Restated 2000 Incentive Plan [Member] | Maximum [Member] | Stock Compensation Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares authorized |  |  | 422,000 |  |
Employee Stock Purchase Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Stock based compensation expense |  |  | $ 21,000 | $ 29,000 | $ 47,000
Shares issued from common stock |  |  | 17,000 |  |
Income tax benefit to stock based compensation |  |  | $ 5,000 | $ 7,000 | $ 11,000
Issue of treasury stock to the ESPP for the offering periods |  |  | 29,000 | 18,000 | 21,000

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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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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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