Note 1 - Significant Accounting Policies - Summary of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Royalty revenue	$ 6,321	$ 1,890
Collaborative and other research and development revenues	3,116	2,930
Revenues	9,437	4,820
US Department of Health and Human Services [Member]
Collaborative and other research and development revenues	654	2,324
Shionogi and Co. Ltd [Member]
Collaborative and other research and development revenues	296	296
Seqirus UK Limited [Member]
Collaborative and other research and development revenues	$ 2,166	$ 310

Represents collaborative and other research and development.

No definition available.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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- Definition

Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

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- Details

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- Details

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