Stockholders' deficit - Warrants Outstanding (Details) - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Stock options
Beginning balance, warrants	2,566,101,248	97,799,908
Beginning balance, warrants exercise price	$ 0.0044700	$ 0.0910
Warrants Granted, shares	152,017,272,726	27,700,652
Warrants granted, price	$ 0.0000324	$ 0.1177
Warrants Forfeited, shares	(2,366,666)	2,456,534,397
Warrants Forfeited, price	$ 0.0300000	$ 0.0020400
Warrant Exercised, shares	(125,609,759)	(15,633,709)
Warrants Exercised, price	$ 0.0009000	$ 0.0300000
Ending Balance, warrants	154,455,397,549	2,566,101,248
Ending Balance, warrants exercise price	$ 0.0000737	$ 0.0044700

No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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- Definition

Number of warrants or rights outstanding.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

Net number of non-option equity instruments granted to participants.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

Number of share options (or share units) exercised during the current period.

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