Note 15 - Fair Value Measurements - Changes in Fair Value Assets (Details) - Corporate Debt Securities [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Balance	$ 4,058	$ 3,339
Additions		2,000
Payments received
Sales		(1,268)
Included in earnings		268
Included in other comprehensive income	(129)	(281)
Balance	$ 3,929	$ 4,058

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-Section 50
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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of gain (loss) recognized in other comprehensive income, arising from assets, liabilities and financial instruments classified in shareholders' equity measured at fair value on a recurring basis using unobservable inputs (level 3).

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