v3.21.1

Income taxes (Details) - USD ($)	3 Months Ended
Income taxes (Details) - USD ($)	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Income Tax Disclosure [Line Items]
U.S. statutory tax rate (percentage)	21.00%
Deferred tax assets, valuation allowance	$ 1,700,000		$ 1,500,000
Net deferred tax assets after valuation allowance	400,000		400,000
Income tax expense	(8,000)	$ 0
Unrecognized tax benefits	$ 0		$ 0
GIBRALTAR
Income Tax Disclosure [Line Items]
Statutory tax rate (percentage)	10.00%
ROMANIA
Income Tax Disclosure [Line Items]
Statutory tax rate (percentage)	16.00%
UNITED KINGDOM
Income Tax Disclosure [Line Items]
Statutory tax rate (percentage)	19.00%

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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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

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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 unrecognized tax benefits.

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[Line Items] for Income Tax Disclosure [Table]

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The applicable statutory tax rate for each jurisdiction in which the Company is subject to tax.

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