Stockholder's deficit - Black Scholes pricing model (Details)	12 Months Ended
Dec. 31, 2019 USD ($)
Expected dividend rate	$ 0
Minimum [Member]
Calculated stock price	5.00%
Risk free interest rate	1.43%
Expected life of warrants (years)	36 months
Expected volatility of underlying stock	164.50%
Maximum [Member]
Calculated stock price	9.00%
Risk free interest rate	2.58%
Expected life of warrants (years)	60 months
Expected volatility of underlying stock	186.70%

Represents stock price.

No definition available.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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- Definition

Disclosure of the weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

+ References

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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