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Note 1 - Significant Accounting Policies and Concentrations of Risk (Details Textual) - USD ($) shares in Thousands |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Nov. 06, 2013 | Jun. 30, 2015 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Mar. 09, 2011
Currency Hedge Agreement [Member] |  |  |  |  |  |
Collateral Already Posted, Aggregate Fair Value |  |  | $ 0 | $ 0 |  |
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member] |  |  |  |  |  |
Derivative, Loss on Derivative |  |  | 564,000 |  |  |
Derivative, Gain on Derivative |  |  | $ 1,654,000 | 5,487,000 | $ 5,294,000 |
JPR Royalty Sub LLC [Member] |  |  |  |  |  |
Revenue Recognition Royalty and Milestone Revenue Recognized |  |  |  |  |  | $ 30,000,000
Maximum [Member] |  |  |  |  |  |
Maturity of Investments |  |  | 3 years |  |  |
Maturity Period of High Quality Marketable Securities |  |  | 3 years |  |  |
Average Maturity Period of High Quality Marketable Securities |  |  | 1 year 180 days |  |  |
Maturity Period of Short Term Investment |  |  | 1 year |  |  |
Average Maturity for Portfolio Investments |  |  | 1 year 180 days |  |  |
Minimum [Member] |  |  |  |  |  |
Maturity Period of Short Term Investment |  |  | 90 days |  |  |
Long-term Investment Maturity, Minimum |  |  | 1 year |  |  |
Certificates of Deposit [Member] |  |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  |  | $ 150,000 |  |  |
Royalty Receivable [Member] |  |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  |  | 59,000 |  |  |
Collateral for Credit [Member] |  |  |  |  |  |
Restricted Cash and Cash Equivalents |  |  | $ 1,403,000 |  |  |
Computer Equipment [Member] |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 3 years |  |  |
Laboratory Equipment, Office Equipment and Software [Member] |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 5 years |  |  |
Furniture and Fixtures [Member] |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 7 years |  |  |
Building [Member] |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 10 years |  |  |
Agreement [Member] | CSL [Member] | RAPIVABMember | Contingent upon EU Marketing Approval [Member] |  |  |  |  |  |
Proceeds from License Fees Received |  | $ 7,000,000 |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVABMember | Revenue from Sale of Inventory to be Recognized When the Inventory Transfer Is Complete [Member] |  |  |  |  |  |
Deferred Revenue, Additions |  | 3,740,000 |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVABMember | Regulatory Support Revenue for Canadian and EU Marketing Approvals, Portion Recognized Ratably Over Expected Period of Involvement [Member] |  |  |  |  |  |
Deferred Revenue, Additions |  | 1,223,000 |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVABMember |  |  |  |  |  |
Proceeds from License Fees Received |  | 33,740,000 |  |  |  |
Revenues |  | 21,777,000 |  |  |  |
Milestone Payment Maximum |  | $ 12,000,000 |  |  |  |
RAPIVABMember | Customer Concentration Risk [Member] | Sales Revenue, Product Line [Member] |  |  |  |  |  |
Concentration Risk, Percentage |  |  | 90.00% |  |  |
PhaRMA Notes Member] |  |  |  |  |  |
Interest Expense |  |  | $ 5,200,000 | 4,998,000 | 4,778,000 |
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax |  |  | 13,000 | 0 |  |
Amortization of Financing Costs |  |  | 439,000 | 439,000 | 439,000 |
Investments and Cash |  |  | 100,858,000 |  |  |
Securities Offered | $ 10,000,000 |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  |  | 1,612,000 | 150,000 |  |
Revenues |  |  | 48,257,000 | 13,608,000 | 17,331,000 |
Advertising Expense |  |  | 103,000 | 290,000 |  |
Interest Expense |  |  | $ 5,200,000 | $ 4,998,000 | $ 4,778,000 |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  |  | 3,524 | 3,991 | 1,430 |

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