Income taxes - Future Tax Asset (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Net operating loss carry forward	$ 24,023,480	$ 20,556,758
Net operating loss utilized		(73,007)
Foreign exchange differential	68,923	(68,925)
Net taxable loss	8,876,008	3,608,654
Valuation allowance	(32,968,411)	(24,023,480)
Net future tax asset	$ 0	$ 0

Repreesnts foreign exchange differential.

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- Definition

Represents net operating loss utilized continuing operations.

+ References

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences.

+ References

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Amount of valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from tax credit carryforwards for which it is more likely than not that a tax benefit will not be realized.

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