Stockholder's deficit - Black Scholes pricing model (Details)	12 Months Ended
Dec. 31, 2018 USD ($)
Minimum [Member]
Calculated stock price	2.00%
Risk free interest rate	2.60%
Expected life of warrants (years)	3 years
Expected volatility of underlying stock	195.00%
Expected dividend rate	$ 0
Maximum [Member]
Calculated stock price	8.00%
Risk free interest rate	2.90%
Expected life of warrants (years)	5 years
Expected volatility of underlying stock	204.00%
Expected dividend rate	$ 0

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

Weighted average expected volatility rate of share-based compensation awards.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 14.D.2)
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