Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Tax year that remains open to examination under enacted tax laws, in YYYY format.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Note 9 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 15,100	$ 19,400
Unrecognized Tax Benefits	9,020	$ 9,242	$ 8,413	$ 6,496
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	$ 0
Open Tax Year	2022 2023 2024 2025
Domestic Tax Jurisdiction [Member]
Operating Loss Carryforwards	$ 374,400
Domestic Tax Jurisdiction [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	22,400
Domestic Tax Jurisdiction [Member] \| Carryforward Subject to Expiration [Member]
Operating Loss Carryforwards	74,100
Domestic Tax Jurisdiction [Member] \| Indefinite Life Carryforwards [Member]
Operating Loss Carryforwards	$ 300,300