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Note 6 - Fair Value (Details Textual) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($)	Dec. 31, 2024 USD ($) $ / shares	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022
Unrealized Gain (Loss) on Investments		$ (18,785)	$ (48,780)	$ (5,552)
Fair Value, Inputs, Level 1 [Member] | Debt Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	$ 5,000
Fair Value, Inputs, Level 1 [Member] | Equity Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3			100
Fair Value, Inputs, Level 3 [Member] | Warrant [Member]
Unrealized Gain (Loss) on Investments		(4,300)	(5,300)
Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member]
Unrealized Gain (Loss) on Investments		(28,100)	(48,400)
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Unrealized Gain (Loss) on Investments		(3,200)	$ (1,600)
Fair Value, Inputs, Level 2 [Member] | Warrant [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3		$ 200
The 2026 Notes [Member]
Debt Instrument, Share Price (in dollars per share) | $ / shares		$ 24.85
The 2026 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Debt Instrument, Fair Value Disclosure		$ 57,200
The 2027 Notes [Member]
Debt Instrument, Share Price (in dollars per share) | $ / shares		$ 24.29
The 2027 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Debt Instrument, Fair Value Disclosure		$ 55,900
The 2031 Convertible Notes [Member] | Fair Value, Inputs, Level 3 [Member]
Debt Instrument, Fair Value Disclosure		19,400
Asset-backed Notes 2022 [Member] | Fair Value, Inputs, Level 3 [Member]
Debt Instrument, Fair Value Disclosure		$ 81,100
Measurement Input, Hypothetical Market Yields [Member]
Debt Instrument, Measurement Input					0.25

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