Note 1 - Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Restricted Cash and Cash Equivalents, Current, Total	$ 4,348		$ 4,348		$ 2,221
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax			1	$ 1
Advertising Expense	1,800	$ 0	3,204	0
Interest Expense, Debt, Total	13,495	2,918	26,399	5,965
Amortization of Debt Financing Costs and Original Issue Discounts	$ 154	$ 341	$ 211	$ 681
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	27,419	14,007	25,871	12,963
Foreign Exchange Contract [Member] | Not Designated as Hedging Instrument [Member]
Derivative, Loss on Derivative				$ 590
Derivative, Gain on Derivative				632
Computer Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)			3 years
Laboratory Equipment, Office Equipment and Software [Member]
Property, Plant and Equipment, Useful Life (Year)			5 years
Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life (Year)			7 years
Trade Accounts Receivable [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	$ 0		$ 0		0
Collaboration Receivables [Member]
Accounts Receivable, Allowance for Credit Loss, Ending Balance	0		0		0
ORLADEYO [Member] | Trade Accounts Receivable [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	20,925		20,925		149
RAPIVAB [Member] | Trade Accounts Receivable [Member]
Accounts Receivable, after Allowance for Credit Loss, Total	182		$ 182		254
Maximum [Member]
Maturity Period of High Quality Marketable Securities (Year)			3 years
Average Maturity Period of High Quality Marketable Securities (Month)			18 months
Maturity Period of Short Term Investment (Month)			12 months
Average Maturity for Portfolio Investments (Month)			18 months
Minimum [Member]
Long-term Investment Maturity, Minimum (Month)			12 months
Royalty Receivable [Member]
Restricted Cash and Cash Equivalents, Current, Total	2,920		$ 2,920		796
Collateral for Credit [Member]
Restricted Cash and Cash Equivalents, Current, Total	1,428		1,428		$ 1,425
Senior Credit Facility [Member] | MidCap Financial Services, LLC [Member]
Line of Credit Facility, Remaining Borrowing Capacity	$ 75,000		$ 75,000
Interest Expense, Debt, Total				$ 2,779