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Note 2 - Royalty Monetizations (Details Textual) $ in Thousands			6 Months Ended
	Dec. 07, 2020 USD ($)	Mar. 09, 2011 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Nov. 30, 2020 ¥ / $
Future Royalties Payable			$ 136,862	$ 124,717
RPI 2019 Intermediate Finance Trust [Member]
Future Royalties Payable				$ 125,000
Accrued Royalties			2,502
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member]
Royalty Purchase Agreement, Royalties, Percentage of Sublicense Revenue in Other Markets	20.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Under $350,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	8.75%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Between $350,000 and $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	2.75%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Over $550,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Key Territories	0.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Under $150,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets	20.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Between $150,000 and $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets	10.00%
RPI 2019 Intermediate Finance Trust [Member] \| ORLADEYO [Member] \| Annual Net Sales Over $230,000 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Annual Net Sales in Other Markets	0.00%
RPI 2019 Intermediate Finance Trust [Member] \| BCX9930 [Member]
Royalty Purchase Agreement, Royalties, Percentage of Global Annual Net Sales	1.00%
RPI 2019 Intermediate Finance Trust [Member] \| Future Royalties Payable [Member]
Proceeds from Issuance of Debt	$ 125,000
Debt Issuance Costs, Net, Total			$ 2,370
Debt Instrument, Interest Rate, Effective Percentage			24.00%
Royalty Financing Obligation Interest Accretion			$ 15,604
PhaRMA Notes Member] \| Currency Hedge Agreement [Member]
Derivative, Forward Exchange Rate (in JPY per USD) \| ¥ / $					100
JPR Royalty Sub LLC [Member] \| PhaRMA Notes Member]
Private Placement of Senior Secured Notes		$ 30,000
Debt Instrument, Interest Rate, Stated Percentage		14.00%
Secured Debt, Total			30,000
Interest Payable			$ 23,874
Percentage of Carrying Amount in Excess of Fair Value			3.00%
JPR Royalty Sub LLC [Member] \| PhaRMA Notes Member] \| Fair Value, Inputs, Level 2 [Member]
Notes Payable, Fair Value Disclosure			$ 30,000
JPR Royalty Sub LLC [Member] \| Royalty Monetization [Member]
Debt Instrument, Face Amount		$ 30,000
Proceeds from Issuance of Secured Debt		22,691
Transaction Costs		4,309
Interest Reserve		$ 3,000