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Amount of tax expense (benefit) allocated to other comprehensive income (loss).

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Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)
Accounts Receivable, Net, Current, Total	$ 3,803				$ 3,972				$ 3,803	$ 3,972
Revenue from Contract with Customer, Including Assessed Tax	3,238	$ 5,317	$ 3,878	$ 3,189	3,889	$ 2,697	$ 2,765	$ 2,347	15,622	11,698	$ 69,429
Other Comprehensive Income (Loss), Tax, Total									0
Restricted Cash and Cash Equivalents, Noncurrent, Total	1,534				1,522				1,534	1,522
Allowance for Doubtful Accounts Receivable, Current, Ending Balance	0								$ 0
Number of Reporting Units									1
Goodwill, Impairment Loss									$ 0	0
Impairment of Intangible Assets (Excluding Goodwill), Total									0	0
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)									23,200
The 1404 Program [Member]
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)									23,200
Money Market Funds [Member]
Cash Equivalents, at Carrying Value, Total	136,100				87,200				136,100	87,200
Bank Time Deposits [Member]
Cash Equivalents, at Carrying Value, Total	$ 1,600				$ 3,400				1,600	3,400
Product and Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax									$ 714	$ 733	59,134
Product and Service, Other [Member] \| RELISTOR License Agreement [Member]
Revenue from Contract with Customer, Including Assessed Tax											50,700
Contract with Customer, Liability, Revenue Recognized											50,000
Revenue from Contract with Customer, Upfront Payment											700
License [Member] \| License Agreement with Bayer [Member]
Revenue from Contract with Customer, Including Assessed Tax											7,000
Contract with Customer, Liability, Revenue Recognized											3,000
Revenue from Contract with Customer, Upfront Payment											$ 4,000
Accounting Standards Update 2014-09 [Member]
Accounts Receivable, Net, Current, Total													$ 35
Accounting Standards Update 2014-09 [Member] \| Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption													$ 35
Accounting Standards Update 2016-02 [Member] \| Subsequent Event [Member]
Operating Lease, Liability, Total												$ 15,300
Operating Lease, Right-of-Use Asset												$ 13,500