Taxes (Components of Deferred Tax Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Net operating loss and tax credit carryforwards
Net operating loss and tax credit carryforwards	$ 57,074	$ 53,092
Depreciation, amortization and impairment of property and equipment	39	61
Stock options	210	153
Right of use asset	(26)	(40)
Lease liability	26	40
Deferred tax assets	57,323	53,306
Valuation allowance for deferred tax assets	(57,323)	(53,306)
Net deferred tax assets	$ 0	$ 0