Goodwill and Purchased Intangibles Assets - Schedule of Purchased Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Mar. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Net Carrying Amount	$ 918	$ 1,312
Developed technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,900	4,900
Accumulated Amortization	(3,982)	(3,588)
Net Carrying Amount	$ 918	$ 1,312

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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

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