Note 11 - Income Taxes (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($)
Minimum State and Franchise Taxes, Expense	$ 12
Domestic Tax Authority [Member]
Operating Loss Carryforwards	70,400
Operating Loss Carryforwards, Subject To Expiration	$ 9,900
Domestic Tax Authority [Member] | Minimum [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2036
Domestic Tax Authority [Member] | Maximum [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2037
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 47,500
Operating Loss Carryforwards, Subject To Expiration	$ 45,600
State and Local Jurisdiction [Member] | Minimum [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2024
State and Local Jurisdiction [Member] | Maximum [Member]
Operating Loss Carryforwards, Expiration Date	Dec. 31, 2043