Note 16 - Stock Option Plan (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Payment Arrangement, Expense	$ 1,100,000	$ 686,000	$ 689,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 1,200,000	$ 300,000	$ 460,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares, Ending Balance (in shares)	237,500	147,500	76,500
Share-based Compensation Arrangement by Share-based Payment Award, Option, Nonvested, Weighted Average Exercise Price, Ending Balance (in dollars per share)	$ 4.28	$ 4.43	$ 6.32
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)	302,744	56,498	200,629
Proceeds from Stock Options Exercised	$ 3,475,000	$ 712,000	$ 2,817,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	3,800,000	278,000	1,200,000
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	485,000	260,000	152,000
Employee Service, Share Based Compensation Tax Expense (Benefit) from Compensation Expense	(873,000)	(26,000)	(78,000)
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 635,000	476,000	332,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 4 months 24 days
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Expense	$ 602,000	425,000	425,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 729,000	$ 266,000	$ 691,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	2 years 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)	60,000
Share Based Compensation Arrangement by Share Based Payment Award, Equity Instruments Other Than Options, Granted at Closing Price (in dollars per share)	$ 17.74
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares)	60,000	14,475
The 2017 Omnibus Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum	30.00%
Share Based Compensation Arrangement by Share Based Payment Award, Minimum Percentage of Fair Market Value Common Stock on Grant Date	100.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)	10 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	981,853

Represents tax expense (benefit) from compensation expense for employee service.

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The closing price of equity instruments other than options granted during the period under share based payment arrangement.

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The minimum percentage of fair value market value of common stock on grant date of awards under the share based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of non-vested options outstanding.

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Number of share options (or share units) exercised during the current period.

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