Note 8 - Stock-based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024
Outstanding, options (in shares)	14,062
Outstanding, weighted average exercise price (in dollars per share)	$ 2.83
Outstanding, weighted average remaining contractual term (Year)	6 years 8 months 1 day	6 years 2 months 23 days
Outstanding, aggregate intrinsic value	$ 7,064	$ 579
Granted, options (in shares)	4,482
Granted, weighted average exercise price (in dollars per share)	$ 3.61
Granted, weighted average remaining contractual term (Year)	9 years 7 months 9 days
Granted, aggregate intrinsic value	$ 2
Exercised, options (in shares)	0
Exercised, weighted average exercise price (in dollars per share)	$ 0
Forfeited/canceled, options (in shares)	0
Forfeited/canceled, weighted average exercise price (in dollars per share)	$ 0
Outstanding, options (in shares)	18,544	14,062
Outstanding, weighted average exercise price per share (in dollars per share)	$ 3.02	$ 2.83
Vested, options (in shares)	8,336
Vested, weighted average exercise price per share (in dollars per share)	$ 3.46
Vested, weighted average remaining contractual term (Year)	5 years 2 months 19 days
Vested, aggregate intrinsic value	$ 2,125		$ 0

Intrinsic value of granted award under share-based payment arrangement. Excludes share and unit options.

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Weighted average remaining contractual term for option awards granted during the period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of share options (or share units) exercised during the current period.

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