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.

No definition available.

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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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- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-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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Fair value of financial instruments - Assumptions used in the Monte Carlo simulation models (Details)	Mar. 31, 2020 $ / shares	Dec. 31, 2019 $ / shares	Jan. 01, 2018
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input			0.024
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input			0.025
Stock price \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	1.72	2.07
Volatility \| Minimum \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	0.500	0.500
Volatility \| Maximum \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	1.245	1.166
Remaining term (years) \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Warrants and rights outstanding, term	2 years 9 months 10 days	3 years 1 month 7 days
Expected dividend yield \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	0	0
Risk-free rate \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	0.003	0.016
Risk-free rate \| Minimum \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input		0.024
Risk-free rate \| Maximum \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input		0.025
Annual acquisition event probability \| Warrants
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	0.300	0.200
Annual acquisition event probability \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	0.150		0.000
Annual acquisition event probability \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement Input	0.300		0.300