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Income Taxes - Summary of Net Deferred Income Tax Liability (Detail) - USD ($) $ in Thousands | Mar. 31, 2018 | Mar. 31, 2017
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Components Of Deferred Tax Assets And Liabilities [Abstract] |  |
Depreciation | $ (1,582) | $ (2,201)
Accrued compensation | 201 | 242
Prepaid pension asset | (969) | (845)
Accrued pension liability | 129 | 175
Accrued postretirement benefits | 160 | 299
Compensated absences | 366 | 601
Inventories | 51 | 1,045
Warranty liability | 108 | 191
Accrued expenses | 429 | 937
Stock-based compensation | 332 | 548
Intangible assets | (1,100) | (5,097)
New York State investment tax credit | 1,074 | 959
Research and development tax credit | 145 |
Net operating loss carryforwards | 271 |
Other | 47 | 79
Deferred Tax Liabilities, gross | (338) | (3,067)
Less: Valuation allowance | (1,074) | (959)
Total | $ (1,412) | $ (4,026)

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