Represents the percentage of warrants exercisable in conjunction with the IPO.

No definition available.

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- Definition

Percentage of warrants that are to expire in conjunction with the IPO, as agreed upon with holders of warrants.

+ References

No definition available.

+ Details

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- Definition

Exercise price per share or per unit 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)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Value of input used to measure outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Warrant liability - Unobservable inputs (Details)	Mar. 07, 2019	Sep. 30, 2019 £ / shares	May 28, 2019 Y $ / shares £ / shares	Dec. 31, 2018 Y $ / shares £ / shares
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Exercise price of warrants		£ 0.01
Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Percentage of warrants exercisable in conjunction with the IPO	50.00%
Percentage of warrants to expire in conjunction with the IPO	50.00%
Risk free rate \| Series A Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability			2.2	2.6
Risk free rate \| Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability			2.1	2.5
Expected term (years) \| Series A Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability \| Y			8.0	8.4
Expected term (years) \| Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability \| Y			5.8	6.25
Expected volatility \| Series A Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability			74.7	75.4
Expected volatility \| Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability			78.2	79.6
Exercise price \| Series A Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability			0.01	0.01
Exercise price \| Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability			0.01	0.01
Fair value of preferred shares or ordinary shares underlying the warrant \| Series A Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability \| $ / shares			12.28	8.61
Fair value of preferred shares or ordinary shares underlying the warrant \| Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability \| $ / shares			12.28	4.15
Probability that the warrants will not be exercisable prior to the IPO \| Series B1 Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value measurement of the warrant liability				50