Components of Property and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Property, Plant and Equipment [Line Items]
Machinery and equipment	$ 19,335us-gaap_MachineryAndEquipmentGross	$ 16,805us-gaap_MachineryAndEquipmentGross
Furniture and fixtures	1,000us-gaap_FurnitureAndFixturesGross	960us-gaap_FurnitureAndFixturesGross
Leasehold improvements	2,874us-gaap_LeaseholdImprovementsGross	1,876us-gaap_LeaseholdImprovementsGross
Construction in progress	1,685us-gaap_ConstructionInProgressGross	1,226us-gaap_ConstructionInProgressGross
Total cost	24,894us-gaap_PropertyPlantAndEquipmentGross	20,867us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation	(15,767)	(13,978)
Property and equipment, net	$ 9,127us-gaap_PropertyPlantAndEquipmentNet	$ 6,889us-gaap_PropertyPlantAndEquipmentNet

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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- Definition

Amount before accumulated depreciation of equipment commonly used in offices and stores that have no permanent connection to the structure of a building or utilities. Examples include, but are not limited to, desks, chairs, tables, and bookcases.

+ References

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- Definition

Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph (b)

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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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