Note 5 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
3 Months Ended | 9 Months Ended | 12 Months Ended | |||||
---|---|---|---|---|---|---|---|---|
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Dec. 31, 2018 |
Jan. 31, 2019 |
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Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term | [1] | 8 years 36 days | 8 years 73 days | |||||
Incentive Plan 2006 [Member] | ||||||||
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 221 | 221 | 77 | 350 | ||||
Share-based Payment Arrangement, Expense, Tax Benefit | $ 0 | $ 0 | $ 0 | $ 0 | ||||
Share Price | $ 9.11 | $ 9.11 | ||||||
Common Stock, Capital Shares Reserved for Future Issuance | 835 | 835 | ||||||
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount | $ 1,400 | $ 1,400 | ||||||
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term | 2 years 328 days | |||||||
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