Note 1 - Summary of Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
US Department of Health and Human Services [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	$ 16,337	$ 9,366	$ 13,585
Green Cross Corporation [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	132
Shionogi and Co. Ltd [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	1,184	$ 1,184	$ 1,184
CSL [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	21,927
Product sales, net	6,291	$ 33
Royalty revenue	2,386	3,025	$ 2,562
Collaborative and other research and development revenues	39,580	10,550	14,769
Revenues	$ 48,257	$ 13,608	$ 17,331

Represents collaborative and other research and development.

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+ 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=26872669&loc=d3e20235-122688

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+ 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=26872669&loc=d3e20235-122688

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+ 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(a))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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