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Employee Benefit Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Mar. 31, 2025 | Mar. 31, 2024 | Mar. 31, 2023
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 | $ 21,351,000 | $ 22,398,000 |
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% |  |
Defined Contribution Plan 401K [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to defined contribution plan | $ 2,455,000 | 1,914,000 | $ 1,904,000
Pension Plans, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions expected during fiscal 2021 | 0 |  |
Annuities purchased | 1,458,000 | 1,452,000 |
Pension expense | $ 547,000 | $ 556,000 | $ (18,000)
Weighted average discount rates used to develop net postretirement benefit cost | 5.27% | 5.03% | 3.66%
Weighted average rate of increase in compensation levels | 3.00% | 3.00% | 3.00%
Projected benefit obligation | $ 23,876,000 | $ 25,042,000 | $ 26,646,000
Net actuarial (gain) loss recognized in accumulated other comprehensive loss, net of income tax | 6,767,000 | 6,847,000 |
Defined Contribution Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Contributions to defined contribution plan | 1,382,000 | 1,237,000 | 1,030,000
Supplemental Executive Retirement Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Pension expense | $ 54,000 | $ 54,000 | $ 74,000
Weighted average discount rates used to develop net postretirement benefit cost | 5.26% | 5.01% | 3.64%
Weighted average rate of increase in compensation levels | 3.00% | 3.00% | 3.00%
Projected benefit obligation | $ 1,019,000 | $ 1,060,000 |
Net actuarial (gain) loss recognized in accumulated other comprehensive loss, net of income tax | $ (89,000) | $ (69,000) |

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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 Average earnings description for calculation of benefits. + References No definition available. + Details
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- Definition Percentage of employee's first 3% salary deferral for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition The employee deferral percentage that receives a 50% employer matching contribution. + References No definition available. + Details
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- Definition The employee salary deferral that receives 100% matching company contribution. + References No definition available. + Details
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- Definition Description of employer matching contributions to the 401K plan. + 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 Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-14A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (j) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of 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)(1) -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 actuarial present value of benefits attributed to service rendered by employee for 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 (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of contribution expected to be received by defined benefit plan from employer in next fiscal year following current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + 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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