Note 3 - Income Taxes - Cash Taxes Paid (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Federal	$ 0
State	11
Foreign	0
Total	11	$ 52
State taxes	11
California Franchise Tax Board [Member]
State	1
State taxes	1
Louisiana Department of Revenue [Member]
State	(1)
State taxes	(1)
New Jersey Department of Revenue [Member]
State	2
State taxes	2
Pennsylvania Department of Revenue [Member]
State	7
State taxes	7
Other State Departments of Revenue [Member]
State	2
State taxes	$ 2

Amount, after income tax refund received, of cash paid to federal (national) tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to foreign tax jurisdiction for tax on income.

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Amount, after income tax refund received, of cash paid to state and local tax jurisdictions for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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