Note 7 - Income Taxes - Other Disclosures Relating to Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate	$ 2,455	$ 5,283
Interest, net of tax benefit, accrued in the Consolidated Balance Sheets	91	1,027
Penalties, accrued in the Consolidated Balance Sheets	74	43
Interest expense recognized in the Consolidated Statements of Operations	36	523
Penalties expense (benefit) recognized in the Consolidated Statements of Operations	$ 31	$ 5

Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319

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Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return.

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Amount of interest expense accrued for an underpayment of income taxes.

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Amount of interest expense for an underpayment of income taxes.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=SL6600010-109319

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