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Amount of conversion of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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No definition available.

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Probability of an initial public offering.

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The vale of each underlying asset in connection with the initial public offering.

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Volatility rate in respect to initial public offering.

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The holders of warrants have right to take shares.

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No definition available.

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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No definition available.

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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.

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No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section 50
-Paragraph 2
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- Definition

Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
-Paragraph 2
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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
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- Definition

Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3(b))
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Significant accounting policies - Fair value of financial instruments (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Dec. 07, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2018	Nov. 30, 2017	Mar. 31, 2017	Jan. 31, 2017	Nov. 18, 2016	Jul. 31, 2016	Feb. 29, 2016	Jan. 29, 2016	Jan. 01, 2016
Fair value of financial instruments
Cash equivalents		$ 78,182		$ 42,608
Note receivable				150
Total		$ 78,182		42,758
Assumptions to Determine the Fair Value
Probability of an Initial Public Offering			40.00%
Initial Public Offering
Assumptions to Determine the Fair Value
Volatility (in percentage)	46.00%
Probability of an Initial Public Offering	100.00%
Series A-2 Preferred Stock
Fair value of financial instruments
Warrants to purchase shares												64,441
Series A-2 Preferred Stock \| Initial Public Offering
Assumptions to Determine the Fair Value
Value of underlying liability	$ 4.67
Series A-3 Preferred Stock
Fair value of financial instruments
Warrants to purchase shares		700,000					700,000	700,000		1,300,000		1,300,000
Series A-3 Preferred Stock \| Initial Public Offering
Assumptions to Determine the Fair Value
Value of underlying liability	4.67
Series B Preferred Stock
Fair value of financial instruments
Warrants to purchase shares									397,530			562,488
Series C Preferred Stock
Fair value of financial instruments
Warrants to purchase shares		111,114			31,283						57,810	226,733
Series C Preferred Stock \| Initial Public Offering
Assumptions to Determine the Fair Value
Value of underlying liability	4.67
Series D Preferred Stock
Fair value of financial instruments
Warrants to purchase shares						38,828
Series D Preferred Stock \| Initial Public Offering
Assumptions to Determine the Fair Value
Value of underlying liability	$ 4.67
Level 1
Fair value of financial instruments
Cash equivalents		$ 78,182		42,608
Total		78,182		42,608
Level 3
Fair value of financial instruments
Note receivable				150
Total				$ 150
Changes in preferred stock warrant liability measured at fair value
Balance at beginning		2,802	$ 5,547
Changes in fair value of warrants		90	307
Warrant exercise		(2,188)	(5,258)
Conversion to warrants to purchase common stock in connection with IPO		(823)
Balance at ending			2,802
Level 3 \| Debt facility
Changes in preferred stock warrant liability measured at fair value
Issuance of warrants		$ 119	128
Level 3 \| Vendor
Changes in preferred stock warrant liability measured at fair value
Issuance of warrants			$ 2,078