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Stockholders' Equity (Deficit) - Additional Information (Detail) - Redeemable Convertible Preferred Stock [Member] $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) $ / shares shares
Class of Stock [Line Items]
Accretion to Redemption value | $	$ 0
Issuance of Series B redeemable convertible preferred stock	10,027,666
Redeemable Stock Excersible On Agreed Upon Milestones [Member]
Class of Stock [Line Items]
Issuance of Series B redeemable convertible preferred stock	21,732,862
Proceeds from Issuance of Convertible Preferred Stock | $	$ 46,900
Series B [Member]
Class of Stock [Line Items]
Issuance of Series B redeemable convertible preferred stock	14,701,054
Issuance of Series B redeemable convertible preferred stock for cash	4,673,388
Issuance of Series B redeemable convertible preferred stock upon conversion of convertible notes	10,027,666
Preferred stock, Par or Stated Value Per Share | $ / shares	$ 2.16

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- Definition

Issuance of Series B redeemable convertible preferred stock for cash.

+ References

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- Definition

Temporary Equity Stock Issued During Period Issues Value on Conversion of Convertible Notes.

+ References

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- Definition

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- Definition

The cash inflow from issuance of preferred stocks identified as being convertible into another form of financial instrument, typically the entity's common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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- Definition

Per share or per unit amount of equity securities issued.

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- Definition

Value of accretion of temporary equity to its redemption value during the period.

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