Income taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Net operating loss carry-forwards	$ 15,884	$ 16,672
Accruals and reserves	351	263
Deferred revenue	116	84
Intangibles	422	486
Other, net	85	42
Fixed Assets
Gross tax assets	16,858	17,547
Valuation allowance	16,858	(17,547)
Net deferred tax assets

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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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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