v3.8.0.1

Note 1 - Organization and Summary of Significant Accounting Policies (Details Textual) $ in Thousands		1 Months Ended	12 Months Ended			27 Months Ended
	Sep. 18, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2017 USD ($)
Inventory Write-down			$ 369
Proceeds From Sale of Royalty and Milestone Rights	$ 65,000	$ 65,000
Royalty Arrangment Maximum Payments	$ 195,000	195,000
Net Proceeds from Sale of Future Royalties		$ 61,200			61,184	$ 61,184
Effective Annual Interest Rate	14.00%	14.00%
Interest Income [Member]
Asset Impairment Charges			$ 0		$ 500
Minimum [Member]
Property, Plant and Equipment, Useful Life			3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life			5 years
Sales Revenue, Net [Member] | Customer Concentration Risk [Member]
Number of Major Customers			2	2	2
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Two Customers [Member]
Concentration Risk, Percentage			100.00%	100.00%	100.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | One Customer [Member]
Concentration Risk, Percentage			79.00%	71.00%	84.00%

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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