Note 5 - Stock-Based Compensation - Stock Option Valuation Assumptions (Details) - Share-Based Payment Arrangement, Option [Member] - $ / shares	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Stock price (in dollars per share)	$ 27.18
Expected volatility	66.30%	74.70%
Risk-free interest rate	4.30%	4.30%
Monte Carlo Input [Member]
Stock price (in dollars per share)	$ 39.49	$ 22.37

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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