Note 1 - Significant Accounting Policies and Concentrations of Risk (Details) - Summary of Revenues (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 1 - Significant Accounting Policies and Concentrations of Risk (Details) - Summary of Revenues [Line Items]
Product sales, net	$ 33us-gaap_SalesRevenueGoodsNet
Royalty revenue	3,025us-gaap_RoyaltyRevenue	2,562us-gaap_RoyaltyRevenue	3,317us-gaap_RoyaltyRevenue
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	10,550	14,769	22,976
Total revenues	13,608us-gaap_Revenues	17,331us-gaap_Revenues	26,293us-gaap_Revenues
U.S. Department of Health and Human Services [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	9,366	13,585	14,026
Shionogi & Co. Ltd. [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues	1,184	1,184	1,184
Mundipharma [Member]
Collaborative and other research and development revenues:
Collaborative and other research and development revenues			$ 7,766

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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

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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

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-Subparagraph (SX 210.5-03.1(e))

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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