Statements of Convertible Preferred Stock and Stockholders' Equity (Deficit) (Parenthetical) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) $ / shares
Convertible Preferred stock per share \| $ / shares	$ 0.001
Series A1 Convertible Preferred Shares
Convertible Preferred stock per share \| $ / shares	$ 35.06
Net issuance cost on equity \| $	$ 84
IPO
Net issuance cost on equity \| $	$ 29,272
Series A Convertible Preferred Stock
Convertible Preferred stock per share \| $ / shares	$ 35.06
Net issuance cost on equity \| $	$ 635

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant