Note 11 - Share-based Compensation (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Deferred Compensation Share-based Arrangements, Liability, Current	$ 182		$ 3,018
Percentage of FID Bonus Settlement of Shares	110.00%
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	$ 200		400
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 7,300
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	328 days
Additional Paid in Capital, Ending Balance	$ 224,091		$ 180,862
Accounting Standards Update 2018-07 [Member]
Deferred Compensation Share-based Arrangements, Liability, Current		$ (2,100)
Additional Paid in Capital, Ending Balance		$ 2,100

Percentage of FID bonus whereby the FID bonus will be settled in shares of common stock.

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- Definition

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(1))
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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

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- Definition

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

+ 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 (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

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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