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Represents long term investment maturity minimum.

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Maturity period of short term investment.

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Represents the number of major customers accounting for 10% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc.

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Revenue recognition royalty and milestone revenue recognized.

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Amount of amortization expense attributable to debt issuance costs.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of increase in the fair value of derivatives recognized in the income statement.

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Amount of decrease in the fair value of derivatives recognized in the income statement.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Note 1 - Significant Accounting Policies (Details Textual) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($) shares	Dec. 31, 2018 USD ($)	Sep. 23, 2016 USD ($)	Mar. 09, 2011 USD ($)
Long-term Line of Credit, Total	$ 49,616		$ 25,372
Restricted Cash and Cash Equivalents, Current, Total	2,394		1,544
Interest Expense, Debt, Total	2,725	$ 2,136
Amortization of Debt Issuance Costs	$ 255	$ 232
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount \| shares	3,406	1,775
RAPIVAB [Member] \| Customer Concentration Risk [Member] \| Revenue, Product and Service Benchmark [Member]
Number of Major Customers	3
RAPIVAB [Member] \| Customer Concentration Risk [Member] \| Revenue, Product and Service Benchmark [Member] \| Three Customers [Member]
Concentration Risk, Percentage	90.00%
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative, Gain on Derivative	$ 406
Derivative, Loss on Derivative		$ 1,804
Currency Hedge Agreement [Member]
Collateral Already Posted, Aggregate Fair Value	$ 0		$ 0
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
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, Total	$ 979
Collateral for Credit [Member]
Restricted Cash and Cash Equivalents, Current, Total	1,415
Senior Credit Facility [Member] \| MidCap Financial Services, LLC [Member]
Long-term Line of Credit, Total	$ 50,000			$ 23,000
JPR Royalty Sub LLC [Member]
Revenue Recognition Royalty and Milestone Revenue Recognized					$ 30,000