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Note 5 - Share Repurchase Program (Details Textual) $ in Millions		3 Months Ended				6 Months Ended	12 Months Ended
	Aug. 13, 2020	Dec. 31, 2022 shares	Sep. 30, 2022 shares	Jun. 30, 2022 USD ($) shares	Mar. 31, 2022 USD ($) shares	Jun. 30, 2025 USD ($) shares	Dec. 31, 2024 shares	Dec. 31, 2023 shares	May 03, 2022 USD ($) shares	Aug. 31, 2020 shares	Aug. 31, 2019 USD ($) shares
Share Repurchase Program, Authorized, Amount \| $									$ 50.0		$ 34.0
Stock Repurchase Program, Number of Shares Authorized to be Repurchased (in shares) \| shares									3,100,000	2,700,000	1,800,000
Stock Repurchased and Retired During Period, Shares (in shares) \| shares		0	0	963,000	1,300,000	0	0	0
Stock Repurchased and Retired During Period, Value \| $				$ 16.8	$ 25.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount \| $						$ 33.2
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased (in shares) \| shares						2,200,000
Stock Split To [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	3
Stock Split from [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	2