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Equity Compensation Plans - Additional Information (Detail) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Aug. 11, 2020 | Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Cash proceeds from the exercise of stock options |  | $ 0 | $ 24 | $ 307
Total intrinsic value of the stock options exercised |  | $ 0 | 10 | 161
Options, stock awards and performance awards available for future grants |  | 453,000 |  |
Stock Compensation Plan [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock based compensation expense |  | $ 817 | 945 | 1,069
Income tax benefit to stock based compensation |  | $ 193 | $ 208 | $ 237
Employee Stock Option [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Stock option awards granted |  | 0 | 0 | 0
Stock options maximum term |  | 10 years |  |
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Restricted stock awarded |  | 113,000 | 83,000 | 53,000
Unrecognized stock-based compensation expense |  | $ 1,877 |  |
Weighted average period for recognize expense |  | 1 year 8 months 1 day |  |
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 |  |
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] |  |  |  |
Restricted stock awarded |  | 113,000 | 83,000 | 53,000
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 | 27,000
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 | 20,000
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 | 6,000
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] |  |  |  |
Stock based compensation expense |  | $ 47 | $ 30 | $ 0
Income tax benefit to stock based compensation |  | $ 11 | $ 7 | $ 0
Maximum discount on purchase price of common stock percentage on fair market value |  | 15.00% |  |
Issue of treasury stock to the ESPP for the offering periods |  | 21,000 | 9,000 | 6,000
Common stock may be purchased |  | 200,000 |  |

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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 The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=120381028&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 http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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