Note 7 - Stock-based Compensation (Details Textual)	9 Months Ended
Sep. 30, 2019 USD ($) $ / shares	Sep. 30, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares	$ 3.77
Share-based Payment Arrangement, Additional Cost	$ 59,000
Incentive Plan [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 921,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	3 years 73 days
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Expense	$ 222,000	$ 413,000
Share-based Payment Arrangement, Option [Member] \| Incentive Plan [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	347,000
Restricted Stock [Member]
Dividend, Share-based Payment Arrangement, Shares	5,000	$ 94,000
Restricted Stock [Member] \| Incentive Plan [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 574,000
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Exercise Price	14.63
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Exercise Price	15.48

Price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount of additional cost recognized for award under share-based payment arrangement from a settlement agreement reached with outgoing President.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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