Note 5 - Income Taxes - Tax Reserves (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Taxes	$ 54	$ 46	$ 42
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	17		$ 16
Unrecognized Tax Benefits, Income Tax Penalties Accrued	15	$ 14
Total Tax Liability	86
State and Local Jurisdiction [Member]
Taxes	54
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	17
Unrecognized Tax Benefits, Income Tax Penalties Accrued	15
Total Tax Liability	86
Domestic Tax Authority [Member]
Taxes	0
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	0
Unrecognized Tax Benefits, Income Tax Penalties Accrued	0
Total Tax Liability	0
Foreign Tax Authority [Member]
Taxes	0
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	0
Unrecognized Tax Benefits, Income Tax Penalties Accrued	0
Total Tax Liability	$ 0