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Note 14 - Stock Based Compensation (Details Textual) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | May 23, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance (in dollars per share) | $ 25.30 | $ 23.39 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term (Year) | 6 years 4 months 24 days |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value | $ 82,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value | $ 71,000 |  |  |
Share Price (in dollars per share) | $ 30.81 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Fair Value |  | $ 49,000 |  |
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount | $ 19,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares) | 0 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price (in dollars per share) | $ 22.60 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term (Year) | 6 years 4 months 24 days |  |  |
Minimum [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance (in dollars per share) | $ 20.86 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price (in dollars per share) | 20.86 |  |  |
Maximum [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price, Ending Balance (in dollars per share) | 27.25 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price (in dollars per share) | $ 27.25 |  |  |
The Stock Incentive Plan of 2012 [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares) |  |  |  | 200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares) | 92,482 |  |  |
Share-based Payment Arrangement, Option [Member] |  |  |  |
Share-based Payment Arrangement, Expense | $ 15,000 | 53,000 | $ 38,000 |
Restricted Stock Units (RSUs) [Member] |  |  |  |
Share-based Payment Arrangement, Expense | $ 157,000 | $ 349,000 | $ 244,000 |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year) | 3 years |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance (in shares) | 18,989 | 9,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding | $ 585,000 | $ 288,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Grant Date Fair Value | $ 306,000 | $ 270,000 |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year) | 1 year 10 months 2 days |  |  |
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount | $ 337,000 |  |  |

X
- Definition The fair value at grant date for nonvested equity-based awards issued 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 No definition available. + Details
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- Definition The grant-date fair value of options granted during the period. + References No definition available. + Details
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- Definition Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(iii) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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