Note 3 - Acquisition of Astero Bio Corporation - Pro Forma Information (Details) - Astero [Member] - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
Total revenue	$ 12,681	$ 9,016
Net income attributable to common stockholders	$ 801	$ 258
Basic (in dollars per share)	$ 0.04	$ 0.02
Diluted (in dollars per share)	$ 0.03	$ 0.01

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-Subparagraph (h)(2)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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