Stockholders' deficit - (Details) - Warrants - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Class of Warrant or Right [Line Items]
Beginning balance, warrants	623,777,506	615,561,379
Exercise price, Beginning balance	$0.000675 to $0.12	$0.000675 to $0.12
Weighted average exercise price Beginning balance	$ 0.0052875	$ 0.011380
Warrants Granted, shares		471,010,103
Exercise price, Granted		$0.0020500
Weighted average exercise price Granted		$ 0.003080
Warrants Forfeited/cancelled, shares	(12,637,500)	(101,682,866)
Exercise price forfeited/cancelled	$0.12	$0.0015 to $0.12
Weighted average exercise price Forfeited/cancelled	$ 0.12	$ 0.039029
Warrant Exercised, shares		(361,111,110)
Exercise Price Exercised		$0.00150 to $0.00205
Weighted average exercise price Exercised		$ 0.003291
Warrant Exercised, shares		361,111,110
Ending Balance, warrants	611,140,006	623,777,506
Exercise price ending balance	$0.000675 to $0.12
Weighted average exercise price Ending balance	$ 0.0029154	$ 0.0052875

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Number of warrants or rights outstanding.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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