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Income Taxes - Summary of Net Deferred Income Tax Liability (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Mar. 31, 2019
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Components Of Deferred Tax Assets And Liabilities [Abstract] |  |
Depreciation | $ (1,707) | $ (1,714)
Accrued compensation | 206 | 230
Prepaid pension asset | (783) | (935)
Accrued pension liability | 169 | 145
Accrued postretirement benefits | 143 | 150
Compensated absences | 402 | 355
Inventories | (13) | 14
Warranty liability | 81 | 80
Accrued expenses | 366 | 267
Equity-based compensation | 385 | 359
Operating lease assets | (58) |
Operating lease liabilities | 60 |
New York State investment tax credit | 1,108 | 1,069
Net operating loss carryforwards | 75 | 50
Capital loss related to sale of Energy Steel | 4,211 | 3,848
Other | 1 | (20)
Deferred Tax Assets, gross | 4,646 | 3,898
Less: Valuation allowance | (5,319) | (4,917)
Total | $ (673) | $ (1,019)

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