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Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Mar. 31, 2017 | Mar. 31, 2016
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Gross Amount | $ 9,228 | $ 9,432
Intangible assets, Accumulated Amortization | (8,927) | (8,578)
Intangible assets, Net Book Value | 301 | 854
Licenses |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Gross Amount | 4,422 | 4,422
Intangible assets, Accumulated Amortization | (4,134) | (3,739)
Intangible assets, Net Book Value | $ 288 | 683
Intangible assets, Estimated Useful Life | 7 years |
Core Technology And Know How |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Gross Amount | $ 4,806 | 5,010
Intangible assets, Accumulated Amortization | (4,793) | (4,839)
Intangible assets, Net Book Value | $ 13 | $ 171
Core Technology And Know How | Minimum |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Estimated Useful Life | 5 years |
Core Technology And Know How | Maximum |  |
Finite Lived Intangible Assets [Line Items] |  |
Intangible assets, Estimated Useful Life | 10 years |

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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