Note 6 - Collaboration Agreement - Summary of Revenue Recognized Under the Amended Agreements (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Non-cash royalty revenue related to Royalty Monetization (See Note 8)		$ 151	$ 7
Royalty revenue	$ 31
Collaboration agreement		7,143	6,440	14,857
Collaborative Arrangement [Member]
License				13,167
Revenue Recognized		269	688	1,690
Non-cash royalty revenue related to Royalty Monetization (See Note 8)		151	7
Royalty revenue		50	3
Collaboration agreement		7,143	6,440	14,857
Collaborative Arrangement [Member] \| ZALVISO [Member] \| Grunenthal [Member]
Revenue Recognized		$ 6,673	$ 5,742

The amount of non-cash royalty revenue recognized in connection to royalty monetization.

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- Definition

The amount of revenue recognized as a result of the revenue allocation under collaboration agreement.

+ References

No definition available.

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- Definition

Revenue recognized from collaboration agreements.

+ References

No definition available.

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- Definition

Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

+ 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

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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

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