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Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Mar. 31, 2016 | Mar. 31, 2015
Income Taxes [Line Items] |  |
Valuation allowance | $ 985 | $ 952
Liability unrecognized tax benefits | $ 0 | $ 0
Earliest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2013 |
Earliest Tax Year [Member] | State Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2011 |
Earliest Tax Year [Member] | International Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2012 |
Latest Tax Year [Member] | Federal Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2015 |
Latest Tax Year [Member] | State Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2015 |
Latest Tax Year [Member] | International Tax Jurisdictions [Member] |  |
Income Taxes [Line Items] |  |
Open tax year | 2015 |
Investment Tax Credit Carryforward [Member] |  |
Income Taxes [Line Items] |  |
Deferred income taxes include the impact of state investment tax credits | $ 311 |
State investment tax credits with an unlimited carryforward period | $ 674 |
Investment Tax Credit Carryforward [Member] | Maximum [Member] |  |
Income Taxes [Line Items] |  |
Expiration date of state investment tax credits | Mar. 31, 2030 |
Investment Tax Credit Carryforward [Member] | Minimum [Member] |  |
Income Taxes [Line Items] |  |
Expiration date of state investment tax credits | Mar. 31, 2016 |

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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
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