Intangible Assets - Schedule of Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Finite Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	$ 9,280	$ 10,209
Intangible assets, Accumulated Amortization	(7,858)	(8,214)
Intangible assets, Net Book Value	1,422us-gaap_FiniteLivedIntangibleAssetsNet	1,995us-gaap_FiniteLivedIntangibleAssetsNet
Licenses
Finite Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	4,422	4,473
Intangible assets, Accumulated Amortization	(3,328)	(2,962)
Intangible assets, Net Book Value	1,094	1,511
Intangible assets, Estimated Useful Life	7 years
Core Technology And Know How
Finite Lived Intangible Assets [Line Items]
Intangible assets, Gross Amount	4,858	5,736
Intangible assets, Accumulated Amortization	(4,530)	(5,252)
Intangible assets, Net Book Value	$ 328	$ 484
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

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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=26713463&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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