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Employee Benefit Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023 | Mar. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employee's years of service and average earnings | five highest consecutive calendar years of compensation in the ten-year period preceding retirement |  |
Accumulated benefit obligation | $ 22,398,000 | $ 23,784,000 |
Contribution equal to employee salary deferral | 100.00% |  |
Employer contribution description | matching contributions equal to 100% of the first 3% of an employee's salary deferral and 50% of the next 2% percent of an employee’s salary deferral |  |
Contribution next to employee salary deferral | 3.00% |  |
Contribution for additional employee salary deferral | 50.00% |  |
Contribution additional next to employee salary deferral | 2.00% |  |
Share of the medical premium cost for family coverage | $ 4,000 |  |
Share of the medical premium cost for single coverage | 2,000 |  |
Share of the medical premium both family and single coverage for regular retirees | $ 1,000 |  |
Medical care cost trend rate | 4.50% |  |
Medical care trend year | 2028 |  |
Medical care cost trend rate decrements | 0.50% |  |
Current portion of accrued postretirement benefit obligation | $ 49,000 | 49,000 |
Defined Contribution Plan 401K [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to defined contribution plan | 1,914,000 | 1,904,000 | $ 1,365,000
Pension Plans, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions expected during fiscal 2021 | 0 |  |
Liability released through annuity purchase | 1,452,000 | 1,383,000 |
Annuities purchased | 1,452,000 | 1,383,000 |
Pension expense | $ 556,000 | $ (18,000) | $ (538,000)
Weighted average discount rates used to develop net postretirement benefit cost | 5.03% | 3.66% | 3.21%
Weighted average rate of increase in compensation levels | 3.00% | 3.00% | 3.00%
Projected benefit obligation | $ 25,042,000 | $ 26,646,000 | $ 32,991,000
Net actuarial (gain) loss recognized in accumulated other comprehensive loss, net of income tax | 6,847,000 | 7,506,000 |
Defined Contribution Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to defined contribution plan | 1,237,000 | 1,030,000 | 710,000
Supplemental Executive Retirement Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension expense | $ 54,000 | $ 74,000 | $ 346,000
Weighted average discount rates used to develop net postretirement benefit cost | 5.01% | 3.64% | 3.21%
Weighted average rate of increase in compensation levels | 3.00% | 3.00% | 3.00%
Projected benefit obligation | $ 1,060,000 | $ 1,104,000 |
Net actuarial (gain) loss recognized in accumulated other comprehensive loss, net of income tax | (69,000) | (47,000) |
Other Postretirement Benefit Plans [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension expense | $ 15,000 | $ 27,000 | $ 38,000
Weighted average discount rates used to develop net postretirement benefit cost | 4.76% | 3.32% | 2.34%
Projected benefit obligation | $ 311,000 | $ 355,000 | $ 478,000
Net actuarial (gain) loss recognized in accumulated other comprehensive loss, net of income tax | $ (2,000) | $ 11,000 |

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- Definition Company's share of the medical premium cost for early retirees for family coverage under the other postretirement plan. + References No definition available. + Details
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- Definition Company's share of the medical premium cost for early retirees for single coverage under the other postretirement plan. + References No definition available. + Details
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- Definition Company's share of the medical premium cost for regular retirees for coverage under the other postretirement plan. + References No definition available. + Details
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- Definition The employer matching contribution percentage on the 2% employee salary deferral after the first 3% employee salary deferral. + References No definition available. + Details
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- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(8) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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