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Note 14 - Share-based Compensation (Details Textual) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2022 USD ($) $ / shares shares | Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) $ / shares shares
Number Of Active Stock Incentive Plans |  | 1 |  |
Number Of Inactive Stock Option Plans |  | 1 |  |
Common Stock, Capital Shares Reserved for Future Issuance (in shares) |  | 873,402 |  |
Common Stock, Capital Shares Reserved for Future Issuance, Percentage Vesting of Outstanding PSAs Assumed |  | 100.00% |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Net of Forfeitures, Total (in shares) |  | 0 | 0 | 0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares) |  | 0 | 0 | 24,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price (in dollars per share) | $ / shares |  |  |  | $ 24.15
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value | $ |  |  |  | $ 0.1
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number, Ending Balance (in shares) |  | 0 | 0 |
Performance Shares [Member] |  |  |  |
Restricted Stock Units and Performance Share Award Target Level, Percentage |  | 100.00% |  |
Performance Awards Issued Multiplier |  |  | 93.00% | 141.00%
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number At Target Level Of Performance (in shares) |  | 149,000 |  |
Performance Share Award Target Level, Percentage |  | 100.00% |  |
Performance Shares [Member] | Minimum [Member] |  |  |  |
Performance Awards Issued Multiplier |  | 0.00% |  |
Performance Shares [Member] | Maximum [Member] |  |  |  |
Performance Awards Issued Multiplier |  | 200.00% |  |
Restricted Stock Units and Performance Stock Awards [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | $ / shares |  | $ 30.68 | $ 33.30 | $ 26.61
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ |  | $ 2.4 | $ 3.3 | $ 2.0
Share-Based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount | $ |  | $ 3.5 |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) |  | 1 year 6 months |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) | [1] | 116,622 |  |
Stock Awards [Member] | Director [Member] |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share) | $ / shares |  | $ 30.75 | $ 30.94 | $ 25.81
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares) |  | 11,380 | 12,606 | 17,442
[1] | The number of PSAs disclosed in this table are at the target level of 100%.

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- Definition 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). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(01) -URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901 + Details
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