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The fair value amount of the equity component of convertible debt which may be settled in cash upon conversion.

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Represents the amount of principal on f a debt instrument that can be converted to another debt instrument.

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No definition available.

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Represents the maximum product of the closing sale price of shares of the entity's common stock and the applicable conversion rate for such trading day.

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No definition available.

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Represents the mandatory prepayment as part of a covenant on a debt instrument.

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Represents the minimum principal amount required to trigger prepayment as part of a covenant on a debt instrument.

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No definition available.

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Represents the conditional additional amount available for open market transactions as part of a debt covenant.

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Percentage of net cash proceeds from equity offering for maximum additional amount allowed to be purchased on open market transactions under the covenant of the debt instrument.

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Represents the maximum amount of initial cash available for open market transactions as part of a debt instrument.

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Represents the unlimited threshold for open market transactions as part of a debt covenant.

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Represents the prepayment premium on covenant on a debt instrument.

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Represents the floor rate on a variable rate debt instrument.

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Period for notice of withdrawal of debt instrument.

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Represents the original issue discount percentage on a debt instrument.

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Represents the basis spread on the variable rate on paid in kind interest on a debt instrument.

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Percentage of interest payable in cash on the debt instrument.

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Percentage of cash proceeds from indebtedness for prepayment on the debt instrument.

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Percentage of cash proceeds from sale or license of assets for prepayments of the debt instrument.

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Percentage of milestone payments received for prepayment of debt instrument.

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Percentage of net cash proceeds from insurance recoveries for prepayment on the debt instrument.

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Represents the annual prepayment percentage on a debt instrument.

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The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Face (par) amount of debt instrument at time of issuance.

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Net increase or decrease in the carrying amount of the debt instrument for the period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage of principal amount of debt redeemed.

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Amount, after accumulated amortization, of debt premium.

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Indicates type of variable interest rate on debt instrument.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Gross amount of debt extinguished.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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The cash outflow for cost incurred in the modification of term of existing debt agreement in order for the entity to achieve some advantage.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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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