Schedule of deferred tax assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Vacation accrual		$ 3
Allowance for related party note receivable	76	69
Net operating loss	11,777	10,187
Property, plant and equipment		6
Stock options	278	31
Research and development tax credit	144	120
Deferred tax assets	12,275	10,416
Valuation allowance	(11,921)	(9,717)
Deferred tax assets, net of valuation allowance	354	699
Deferred tax liabilities:
Property, plant and equipment	(61)
Intangibles	(10,570)
Deferred tax liabilities	(10,631)
Deferred tax (liabilities) assets	$ (10,277)	$ 699