Note 18 - Stock-based Compensation (Details Textual) - USD ($)		3 Months Ended		12 Months Ended
		Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2018	Dec. 31, 2021
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized							500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	[1]			1,037,000
Proceeds (Used for) and Received from Settlement of Stock Awards				$ 203,000	$ 175,000
Common Stock, Capital Shares Reserved for Future Issuance				112,000
Share-based Compensation Arrangement by Share-based Payment Award, Expected Shares to be Awarded				115,000
Stock Appreciation Rights (SARs) [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	[1]			1,037,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period				10 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period				42,000	29,000	34,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number				340,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Exercise Price				$ 43.41
Stock Appreciation Rights (SARs) [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Exercise Price				25.76	$ 19.44	$ 19.37		$ 15.24
Stock Appreciation Rights (SARs) [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Exercise Price				$ 74.92	$ 74.92	$ 74.92		$ 50.71
Stock Appreciation Rights (SARs) [Member] | Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage				20.00%
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period				5 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period				46,000	38,000	35,000
Common Stock, Capital Shares Reserved for Future Issuance				102,000
Performance Shares [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period				3 years
Sharebased Compensation Arrangement by Share-based Payment Award Post Vesting Holding Period				1 year
Share-based Compensation Arrangement by Share-based Payment Award Liquidity Discount				5.80%	5.20%	5.80%
Performance Shares [Member] | Minimum [Member]
Common Stock, Capital Shares Reserved for Future Issuance				0
Performance Shares [Member] | Maximum [Member]
Common Stock, Capital Shares Reserved for Future Issuance				205,000
Restricted Stock Units (RSUs) [Member]
Common Stock, Capital Shares Reserved for Future Issuance				10,000
Restricted Stock Units (RSUs) [Member] | Director [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period				12 months
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period		9,550	8,668
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Fair Value Granted		$ 500,000	$ 550,000

[1] Under the 2015 Omnibus Equity Compensation Plan, shares of stock are authorized for issuance as incentive and non-qualified stock options, SARs, RSAs, and RSUs.