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Note 17 - Share-Based Compensation and Other Benefit Programs - Non-Qualified Stock Options (Details) - Non-Qualified Stock Options - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding, Beginning of Period, Number of Shares	981,547
Outstanding, Beginning of Period, Weighted Average Exercise Price Per Share	$ 10.05
Exercised, Number of Shares	(207,598)
Exercised, Weighted Average Exercise Price Per Share	$ 7.50
Forfeited, Number of Shares	0
Forfeited, Weighted Average Exercise Price Per Share	$ 0
Expired, Number of Shares	(430)
Expired, Weighted Average Exercise Price Per Share	$ 18.42
Outstanding, End of Period, Number of Shares	773,519	981,547
Outstanding, End of Period, Weighted Average Exercise Price Per Share	$ 10.73	$ 10.05
Weighted Average Remaining Contractual Term, Outstanding	3 years 2 months 12 days
Total intrinsic value of options outstanding	$ 7,366
Exercisable, Number of Shares	773,519
Exercisable, Weighted Average Exercise Price Per Share	$ 10.73
Weighted Average Remaining Contractual Term, Exercisable	3 years 2 months 12 days
Total intrinsic value of options exercisable	$ 7,366
Share Price	$ 20.25
Aggregate intrinsic value of options exercised	$ 3,344	$ 4,984	$ 6,274
Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options	702	1,047	1,318
Proceeds from Stock Options Exercised	$ 1,553	$ 2,416	$ 1,425
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	4 years
2020 Award Year
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Granted, Number of Shares	0
Granted, Weighted Average Exercise Price Per Share	$ 0
2019 Award Year
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Granted, Number of Shares		0
2018 Award Year
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Granted, Number of Shares			0
Share-based Compensation Award, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%
Share-based Compensation Award, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	50.00%