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Income Taxes - Summary of Net Deferred Income Tax Liability (Detail) - USD ($) $ in Thousands | Mar. 31, 2021 | Mar. 31, 2020
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Components Of Deferred Tax Assets And Liabilities [Abstract] |  |
Depreciation | $ (1,772) | $ (1,707)
Accrued compensation | 147 | 206
Prepaid pension asset | (1,386) | (783)
Accrued pension liability | 347 | 169
Accrued postretirement benefits | 131 | 143
Compensated absences | 435 | 402
Inventories | 462 | (13)
Warranty liability | 140 | 81
Accrued expenses | 585 | 366
Equity-based compensation | 337 | 385
Operating lease assets | (22) | (58)
Operating lease liabilities | 23 | 60
New York State investment tax credit | 1,115 | 1,108
Net operating loss carryforwards |  | 75
Capital loss related to sale of Energy Steel | 4,211 | 4,211
Other | (62) | 1
Deferred Tax Assets, gross | 4,691 | 4,646
Less: Valuation allowance | (5,326) | (5,319)
Total | $ (635) | $ (673)

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