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Note 7 - Debt (Details Textual) - USD ($) $ in Thousands		3 Months Ended
Note 7 - Debt (Details Textual) - USD ($) $ in Thousands	Dec. 07, 2020	Mar. 31, 2022	Mar. 31, 2021
MidCap Financial Services, LLC [Member] \| Senior Credit Facility [Member]
Repayments of Lines of Credit	$ 43,298
Credit Agreement [Member] \| Athyrium [Member]
Debt Instrument, Face Amount	$ 200,000
Debt Instrument, LIBOR Floor	1.75%
Debt Instrument, LIBOR Cap	3.50%
Debt Instrument, Exit Fee, Percentage of Principal	2.00%
Debt Instrument, Commitment Fee Percentage	1.00%
Long-term Debt, Gross		$ 125,000
Paid-in-Kind Interest		4,321	$ 3,549
Long-Term Debt, Total		$ 146,386
Debt Instrument, Interest Rate, Effective Percentage		12.17%
Credit Agreement [Member] \| Athyrium [Member] \| Prior to the Second Anniversary [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	102.00%
Debt Instrument, Prepayment Fee, Percentage of Accrued Interest	0.50%
Credit Agreement [Member] \| Athyrium [Member] \| Between the Second and Third Anniversaries [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	2.00%
Credit Agreement [Member] \| Athyrium [Member] \| Between the Third and Fourth Anniversaries [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	1.00%
Credit Agreement [Member] \| Athyrium [Member] \| After Fourth Anniversary [Member]
Debt Instrument, Prepayment Fee, Percentage of Principal Voluntary Payments	0.00%
Credit Agreement [Member] \| Athyrium [Member] \| Term Loan A Drawn [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	$ 15,000
Credit Agreement [Member] \| Athyrium [Member] \| Term Loan A and B Drawn [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	20,000
Credit Agreement [Member] \| Athyrium [Member] \| Term Loans A, B and C Drawn [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	15,000
Credit Agreement [Member] \| Athyrium [Member] \| Term Loans A, B and C Drawn and Cure Right Exercised [Member]
Debt Instrument, Covenant, Minimum Unrestricted Cash and Cash Equivalents	$ 20,000
Credit Agreement [Member] \| Athyrium [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	8.25%
Credit Agreement [Member] \| Athyrium [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| PIK Interest Payment is Made [Member]
Debt Instrument, Basis Spread on Variable Rate	10.25%
Credit Agreement [Member] \| Athyrium [Member] \| Term A Loan [Member]
Proceeds from Issuance of Long-term Debt, Total	$ 125,000
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net, Total		$ 8,651
Amortization of Debt Issuance Costs		$ 167	$ 58
Credit Agreement [Member] \| Athyrium [Member] \| Term B Loan [Member]
Debt Instrument, Face Amount	25,000
Credit Agreement [Member] \| Athyrium [Member] \| Term C Loan [Member]
Debt Instrument, Face Amount	$ 50,000