Stockholders' Equity - Summary of Common Stock Reserved for Future Issuance (Detail) shares in Thousands	Sep. 30, 2019 shares
Equity [Abstract]
Warrants to purchase common stock	13
Common stock options issued and outstanding	2,094
Common stock authorized for future option grants	3,071
RSUs outstanding	1,540
Common stock authorized for the ESPP	489
Total	7,207

Common stock reserved for future issuance, restricted stock units outstanding.

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- Definition

Aggregate number of common shares under ESPP reserved for future issuance.

+ References

No definition available.

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- Definition

Aggregate number of common shares under stock option and restricted stock unit grants reserved for future issuance.

+ References

No definition available.

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- Definition

Number of warrants or rights outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

+ References

No definition available.

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