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Note 1 - Significant Accounting Policies and Concentrations of Risk (Details Textual) shares in Thousands, $ in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2015 USD ($) | Mar. 31, 2016 USD ($) | Dec. 31, 2016 USD ($) shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) shares | Sep. 30, 2016 USD ($) | Sep. 23, 2016 USD ($) | Mar. 09, 2011 USD ($)
Long-term Line of Credit |  |  | $ 22,777 |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  |  | 1,546 | 1,612 |  |  |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax |  |  | 11 | 13 |  |  |  |
Revenues |  |  | 26,353 | 48,257 | $ 13,608 |  |  |
Advertising Expense |  |  |  | 103 | 290 |  |  |
Interest Expense |  |  | 6,487 | 5,200 | 4,998 |  |  |
Amortization of Debt Issuance Costs |  |  | 558 | 439 | $ 439 |  |  |
Property, Plant and Equipment, Gross |  |  | 14,839 | 19,354 |  |  |  |
Lease Financing Obligation, Net of Current |  |  | $ 2,704 | $ 2,375 |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares |  |  | 1,226 | 3,524 | 3,991 |  |  |
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member] |  |  |  |  |  |  |  |
Derivative, Loss on Derivative |  |  | $ 1,654 | $ 564 |  |  |  |
Derivative, Gain on Derivative |  |  | 811 | 1,654 | $ 5,487 |  |  |
Birmingham Research Facility [Member] |  |  |  |  |  |  |  |
Interest Expense |  |  | 408 |  |  |  |  |
Lease Financing Obligation, Net of Current |  |  | 2,704 | 2,375 |  |  |  |
Capital Leases, Future Minimum Payments Due |  |  | $ 4,768 |  |  |  |  |
RAPIVAB [Member] | Customer Concentration Risk [Member] | Sales Revenue, Product Line [Member] |  |  |  |  |  |  |  |
Number of Major Customers |  |  | 3 |  |  |  |  |
RAPIVAB [Member] | Customer Concentration Risk [Member] | Sales Revenue, Product Line [Member] | Three Customers [Member] |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  | 90.00% |  |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVAB [Member] |  |  |  |  |  |  |  |
Proceeds from License Fees Received | $ 33,740 |  |  |  |  |  |  |
Revenues | 21,777 |  |  |  |  |  |  |
Milestone Payment Maximum | 12,000 |  |  |  |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVAB [Member] | Revenue from Sale of Inventory to be Recognized When the Inventory Transfer Is Complete [Member] |  |  |  |  |  |  |  |
Deferred Revenue, Additions | 3,740 |  |  |  |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVAB [Member] | Regulatory Support Revenue for Canadian and EU Marketing Approvals, Portion Recognized Ratably Over Expected Period of Involvement [Member] |  |  |  |  |  |  |  |
Deferred Revenue, Additions | 1,223 |  |  |  |  |  |  |
Agreement [Member] | CSL [Member] | RAPIVAB [Member] | Contingent upon EU Marketing Approval [Member] |  |  |  |  |  |  |  |
Proceeds from License Fees Received | $ 7,000 |  |  |  |  |  |  |
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 |  |  |  |  |
Property, Plant and Equipment, Gross |  |  | $ 540 | 718 |  |  |  |
Leasehold Improvements [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Gross |  |  | $ 8,294 | 5,610 |  |  |  |
Leasehold Improvements [Member] | Birmingham Research Facility [Member] |  |  |  |  |  |  |  |
Property, Plant and Equipment, Useful Life |  |  | 20 years 182 days |  |  |  |  |
Property, Plant and Equipment, Gross |  |  | $ 1,589 | $ 1,589 |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
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 |  |  |  |  |
Royalty Receivable [Member] |  |  |  |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  |  | $ 141 |  |  |  |  |
Collateral for Credit [Member] |  |  |  |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  |  | $ 1,405 |  |  |  |  |
Debt Issuance Costs Reclassifed from Other Current Assets [Member] | December 31, 2015 [Member] |  |  |  |  |  |  |  |
Prior Period Reclassification Adjustment |  | $ 2,196 |  |  |  |  |  |
Senior Credit Facility [Member] | MidCap Financial Services, LLC [Member] |  |  |  |  |  |  |  |
Long-term Line of Credit |  |  |  |  |  | $ 23,000 | $ 23,000 |
JPR Royalty Sub LLC [Member] |  |  |  |  |  |  |  |
Revenue Recognition Royalty and Milestone Revenue Recognized |  |  |  |  |  |  |  | $ 30,000

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