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Note 1 - Significant Accounting Policies and Concentrations of Risk (Details Textual) - USD ($) shares in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2015 | Mar. 31, 2016 | Mar. 31, 2015 | Dec. 31, 2015 | 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 |  | 2,753,000 |  |  |
Derivative, Gain on Derivative |  |  | $ 464,000 |  |
JPR Royalty Sub LLC [Member] |  |  |  |  |
Revenue Recognition Royalty and Milestone Revenue Recognized |  |  |  |  | $ 30,000,000
Debt Issuance Costs Reclassifed from Other Current Assets [Member] | December 31, 2015 [Member] |  |  |  |  |
Prior Period Reclassification Adjustment |  | 2,196,000 |  |  |
Royalty Receivable [Member] |  |  |  |  |
Restricted Cash and Cash Equivalents, Current |  | 562,000 |  |  |
Collateral for Credit [Member] |  |  |  |  |
Restricted Cash and Cash Equivalents |  | $ 1,403,000 |  |  |
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 |  |  |
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 |  |  |
Leasehold Improvements [Member] | Birmingham Research Facility [Member] |  |  |  |  |
Property, Plant and Equipment, Useful Life |  | 20 years 182 days |  |  |
Property, Plant and Equipment, Gross |  | $ 1,589,000 |  |  |
Lease Financing Obligation, Net of Current |  | 2,506,000 |  |  |
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 |  | 1,338,000 | 1,315,000 |  |
Birmingham Research Facility [Member] |  |  |  |  |
Interest Expense |  | 132,000 |  |  |
Capital Leases, Future Minimum Payments Due |  | 4,839,000 |  |  |
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax |  | 0 | 8,000 |  |
Amortization of Debt Issuance Costs |  | 110,000 | 110,000 |  |
Investments and Cash |  | $ 78,915,000 |  |  |
Maturity of Investments |  | 3 years |  |  |
Restricted Cash and Cash Equivalents, Current |  | $ 1,965,000 |  | $ 1,612,000 |
Revenues |  | 4,820,000 | 6,826,000 |  |
Interest Expense |  | 1,470,000 | $ 1,315,000 |  |
Lease Financing Obligation, Net of Current |  | $ 2,506,000 |  | $ 2,375,000 |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  | 1,330 | 3,529 |  |

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