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v3.24.3

Note 6 - Debt (Details Textual) $ / shares in Units, shares in Millions |  |  | 1 Months Ended | 4 Months Ended | 9 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jun. 03, 2024 USD ($) | Nov. 15, 2023 USD ($) | Jul. 31, 2024 USD ($) | Sep. 30, 2024 USD ($) $ / shares | Sep. 30, 2024 USD ($) $ / shares shares | Sep. 30, 2023 USD ($) | Jun. 03, 2026 | Nov. 01, 2025 USD ($) | Jun. 03, 2025 | Dec. 31, 2023 USD ($)
Payments of Debt Restructuring Costs |  |  |  |  | $ 21,179,000 | $ (0) |  |  |  |
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] | us-gaap:SecuredOvernightFinancingRateSofrMember |  |  |  |  |  |  |  |  |
Conversion of 2026 Notes into New Term Loans [Member] |  |  |  |  |  |  |  |  |  |
Payments of Debt Restructuring Costs | $ 21,200,000 |  | $ 600,000 | $ 21,200,000 |  |  |  |  |  |
Debt Conversion, Original Debt, Amount | 118,100,000 |  |  |  |  |  |  |  |  |
Proceeds from Issuance of Debt | $ 88,300,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed | 75.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Increase (Decrease), Net | $ 51,000,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Unamortized Premium | $ 29,800,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage | 5.25% |  |  |  |  |  |  |  |  |
Debt Conversion, Converted Instrument, Amount | $ 67,100,000 |  |  |  |  |  |  |  |  |
Convertible Senior Notes 2026 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible Principal Amount | 14,900,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 5.25% | 5.25% |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 5.89% | 5.89% |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares |  |  |  | $ 18.4875 | $ 18.4875 |  |  |  |  |
Debt Issuance Costs, Net |  |  |  | $ 830,000 | $ 830,000 |  |  |  |  | $ 2,769,000
Debt Instrument, Convertible, Conversion Ratio |  |  |  |  | 54.0906 |  |  |  |  |
Debt Instrument, Convertible Debt, Denominator Amount |  |  |  | 1,000 | $ 1,000 |  |  |  |  |
Debt Conversion, Converted Instrument, Shares Issued | shares |  |  |  |  | 12.2 |  |  |  |  |
Debt Instrument, Convertible, Fair Value Amount of Equity Component |  |  |  | $ 23,200,000 | $ 23,200,000 |  |  |  |  |
Convertible Senior Notes 2026 [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares |  |  |  | $ 18.49 | $ 18.49 |  |  |  |  |
Convertible Senior Notes 2026 [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares |  |  |  | 26.1 | 26.1 |  |  |  |  |
Convertible Senior Notes 2026 [Member] | Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Conversion Price | $ / shares |  |  |  | $ 18.49 | $ 18.49 |  |  |  |  |
Convertible Senior Notes 2026 [Member] | Debt Conversion After September 30, 2020 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger |  |  |  |  | 130.00% |  |  |  |  |
Debt Instrument, Convertible, Threshold Sale Price Of Common Stock Conversion Rate Product Percentage Maximum |  |  |  | 98.00% | 98.00% |  |  |  |  |
Convertible Senior Notes 2026 [Member] | Debt Conversion On Or After August 15, 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger |  |  |  |  | 130.00% |  |  |  |  |
Convertible Senior Notes 2023 [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  | 6.25% |  |  |  |  |  |  |  |
Extinguishment of Debt, Amount |  | $ 95,000,000 |  |  |  |  |  |  |  |
The Credit and Guaranty Agreement [Member] |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 92,100,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Floor on Variable Rate | 3.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 8.75% |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Stated Percentage |  |  |  | 13.87% | 13.87% |  |  |  |  |
Debt Instrument, Percentage of Interest Payable in Cash | 50.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Paid In Kind, Basis Spread on Variable Rate | 10.25% |  |  |  |  |  |  |  |  |
Debt Instrument, Interest Rate, Effective Percentage |  |  |  | 1.52% | 1.52% |  |  |  |  |
Debt Instrument, Prepayment, Percentage of Milestone Payments Received | 25.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Prepayment, Percentage of Cash Proceeds From Sale or License of Assets | 60.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Prepayment, Percentage of Cash Proceeds From Indebtedness | 100.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Prepayment, Percentage of Net Cash Proceeds From Insurance Recoveries | 100.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Prepayments, Annual Prepayment Percentage | 5.00% |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Required Unrestricted Cash | $ 25,000,000 |  |  | $ 25,000,000 | $ 25,000,000 |  |  |  |  |
Debt Instrument, Covenant, Open Market Transactions, Maximum Amount of Initial Cash | 25,000,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Open Market Transactions, Conditional Additional Amount | 10,000,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Open Market Transactions, Unlimited Threshold | $ 38,500,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Open Market Transactions, Maximum Additional Amount, Percentage of Proceeds From Equity Offering | 50.00% |  |  |  |  |  |  |  |  |
Long-Term Debt, Fair Value |  |  |  | $ 69,500,000 | $ 69,500,000 |  |  |  |  |
The Credit and Guaranty Agreement [Member] | Narsoplimab [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Prepayment, Percentage of Cash Proceeds From Sale or License of Assets | 100.00% |  |  |  |  |  |  |  |  |
The Credit and Guaranty Agreement [Member] | Forecast [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Covenant, Minimum Principal Amount Required to Trigger Prepayment |  |  |  |  |  |  |  | $ 38,500,000 |  |
Debt Instrument, Covenant, Mandatory Prepayment |  |  |  |  |  |  |  | 20,000,000 |  |
Debt Instrument, Covenant, Prepayment Premium |  |  |  |  |  |  |  | $ 1,000,000 |  |
Debt Instrument, Prepayments, Annual Prepayment Percentage |  |  |  |  |  |  | 3.00% |  | 5.00% |
The Credit and Guaranty Agreement [Member] | Delayed Draw Term Loan (DDTL) [Member] |  |  |  |  |  |  |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 25,000,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount | $ 25,000,000 |  |  |  |  |  |  |  |  |
Debt Instrument, Notice for Withdrawal Period | 30 days |  |  |  |  |  |  |  |  |
Debt Instrument, Original Issue Discount Percentage | 3.00% |  |  |  |  |  |  |  |  |
The Credit and Guaranty Agreement [Member] | Initial Term Loan [Member] |  |  |  |  |  |  |  |  |  |
Debt Instrument, Face Amount | $ 67,100,000 |  |  |  |  |  |  |  |  |

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