v3.20.1

Income taxes: (Details) - Provision for Income Taxes - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Provision for Income Taxes [Abstract]
Computed expected benefit of income taxes	$ (1,891,163)	$ (865,648)
Stock-based compensation	1,286,201	332,082
Non-deductible interest expense	25,722	25,658
Impact of change in tax rate		5,163,267
Expiry of tax credits	18,486
True up of prior year balances	37,917
Increase (decrease) in valuation allowance	522,837	(4,655,359)
Income tax provision

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Amount of increase (decrease) in valuation and qualifying accounts and reserves.

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