Income Taxes, Deferred Tax Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Deferred Tax Assets [Abstract]
Net operating loss carryforwards	$ 42,484	$ 38,323
Net operating loss carryforwards - foreign	27	24
Excess of tax basis over book value of property and equipment	70	9
Excess of tax basis over book value of intangible assets	1,162	1,325
Lease liability	192	150
Stock-based compensation	1,495	1,487
Accrued employee compensation	338	750
Capitalized equity costs	235	0
Capitalized research and development	1,273	116
Net change in reserve accounts	0	1,031
Gross deferred tax assets	47,276	43,215
Valuation Allowance	(47,096)	(43,070)
Net Deferred Tax Asset	180	145
Deferred Tax Liabilities [Abstract]
Right-of-use asset	(180)	(145)
Gross deferred tax liability	(180)	(145)
TOTAL	0	0
Capitalized R&D costs	1,300
Income Tax Penalties and Interest Expense [Abstract]
Income tax penalties	0	0
Interest on income taxes	$ 0	0
Earliest Tax Year [Member]
Operating Loss Carryforwards [Abstract]
Operating loss carryforwards, expiry date	Dec. 31, 2024
Latest Tax Year [Member]
Operating Loss Carryforwards [Abstract]
Operating loss carryforwards, expiry date	Dec. 31, 2025
U.S. Federal [Member]
Deferred Tax Liabilities [Abstract]
Capitalized R&D, amortization period	5 years
Operating Loss Carryforwards [Abstract]
Net operating loss carryforwards							$ 77,900
Operating loss carryforwards, expiry date	Dec. 31, 2043
Operating loss carryforwards limited with no expiration	$ 99,900	$ 99,900	$ 99,900	$ 99,900	$ 99,900	$ 99,900
Outside U.S. [Member]
Deferred Tax Liabilities [Abstract]
Capitalized R&D, amortization period	15 years
Operating Loss Carryforwards [Abstract]
Net operating loss carryforwards	$ 100
State [Member]
Operating Loss Carryforwards [Abstract]
Operating loss carryforwards limited with no expiration	$ 75,100