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Note 17 - Shareholders' Equity (Details Textual) - USD ($) $ in Millions	1 Months Ended			12 Months Ended
	Sep. 30, 2022	May 31, 2022	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Feb. 01, 2022	Jun. 02, 2021
Common Stock, Capital Shares Reserved for Future Issuance (in shares)								2,689,909
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)				2,121,419
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)				0	0	0
Employee Stock Ownership Plan (ESOP), Shares in ESOP, Total (in shares)				1,021,194
Share Purchase Program [Member]
Stock Repurchase Program, Authorized Amount							$ 300.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount				$ 231.5
Stock Repurchased During Period, Shares (in shares)	366,785	1,320,568	611,000
Stock Repurchased During Period, Value	$ 10.0	$ 40.0	$ 18.5
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				3 years
Share-Based Payment Arrangement, Expense				$ 7.5	$ 6.6	$ 6.4
Share-Based Payment Arrangement, Expense, after Tax				5.6	4.9	4.7
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value				7.6	$ 6.8	$ 6.5
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount				$ 8.2
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 4 months 24 days