Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Note 5 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended			3 Months Ended
	Oct. 31, 2020	Apr. 30, 2019	Jan. 31, 2018	Mar. 31, 2021	Mar. 31, 2020
Proceeds from Stock Options Exercised				$ 31	$ 29
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 407
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				10 months 24 days
Restricted Stock [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total				$ 50
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)				1 year 9 months 18 days
Restricted Stock [Member] \| The 2014 Long-term Incentive Plan [Member]
Stock Issued During Period, Shares, Restricted Stock Award, Gross (in shares)	5,000	20,000	17,500
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)	$ 6.08	$ 11.12	$ 7.16
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)			3 years