Note 19 - Equity Incentive Plans (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Proceeds from Stock Options Exercised	$ 0	$ 838,000	$ 1,094,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		35,880	46,790
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	0	$ 718,000
Share-based Payment Arrangement, Expense	6,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 9,300,000	9,800,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	1 year 10 months 24 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Share-based Payment Arrangement, Expense	$ 6,600,000	$ 7,300,000	$ 5,200,000
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Performance-based Restricted Stock Units [Member] \| Minimum [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	0.00%
Performance-based Restricted Stock Units [Member] \| Maximum [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage	150.00%
2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2,398,672

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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