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Note 7 - Stock Plans (Details Textual) - $ / shares $ / shares in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2015	Dec. 31, 2023
Common Stock, No Par Value (in dollars per share)		$ 0			$ 0
Stock Settled Stock Appreciation Rights SSARs [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Exercised (in shares)		(0)	7,665
The 2022 Stock Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)		500,000
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Vesting Each Year [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		33.00%
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Award Date Three [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		1 year
The 2022 Stock Incentive Plan [Member] \| Restricted Stock [Member] \| Award Date Two [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		3 years
Long-Term Incentive Plan [Member] \| Stock Settled Stock Appreciation Rights SSARs [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)				10 years
Long-Term Incentive Plan [Member] \| Restricted Stock [Member] \| New Employee [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)	1,000
The 2002 Employee Stock Purchase Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)		165,000
Shares, Issued (in shares)		108,591