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Income Taxes - Summary of Net Deferred Income Tax Liability (Detail) - USD ($) $ in Thousands | Mar. 31, 2019 | Mar. 31, 2018
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Components Of Deferred Tax Assets And Liabilities [Abstract] |  |
Depreciation | $ (1,714) | $ (1,582)
Accrued compensation | 230 | 201
Prepaid pension asset | (935) | (969)
Accrued pension liability | 145 | 129
Accrued postretirement benefits | 150 | 160
Compensated absences | 355 | 366
Inventories | 14 | 51
Warranty liability | 80 | 108
Accrued expenses | 267 | 429
Stock-based compensation | 359 | 332
Intangible assets |  | (1,100)
New York State investment tax credit | 1,069 | 1,074
Research and development tax credit |  | 145
Net operating loss carryforwards | 50 | 271
Capital loss related to subsidiary held for sale | 3,848 |
Other | (20) | 47
Deferred Tax Assets, gross | 3,898 |
Deferred Tax Liabilities, gross |  | (338)
Less: Valuation allowance | (4,917) | (1,074)
Total | $ (1,019) | $ (1,412)

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