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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016
Income Taxes [Line Items] |  |
Valuation allowance | $ 959 | $ 985
Liability unrecognized tax benefits | $ 0 | $ 0
Earliest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2014 |
Earliest Tax Year [Member] | State Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2012 |
Earliest Tax Year [Member] | International Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2013 |
Latest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2016 |
Latest Tax Year [Member] | State Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2016 |
Latest Tax Year [Member] | International Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2016 |
Other Assets [Member] |  |
Income Taxes [Line Items] |  |
Deferred income tax asset foreign | $ 25 |
Investment Tax Credit Carryforward [Member] |  |
Income Taxes [Line Items] |  |
Deferred income taxes include the impact of state investment tax credits | 305 |
State investment tax credits with an unlimited carryforward period | $ 654 |
Investment Tax Credit Carryforward [Member] | Maximum [Member] |  |
Income Taxes [Line Items] |  |
Expiration date of state investment tax credits | Mar. 31, 2031 |
Investment Tax Credit Carryforward [Member] | Minimum [Member] |  |
Income Taxes [Line Items] |  |
Expiration date of state investment tax credits | Mar. 31, 2017 |

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