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Note 6 - Fair Value (Details Textual) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025 USD ($) $ / shares	Sep. 30, 2024 USD ($)	Sep. 30, 2025 USD ($) $ / shares	Sep. 30, 2024 USD ($)	Jun. 30, 2022
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3				$ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	$ 0		$ 0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	(2,617)	$ 0	(2,617)
Unrealized Gain (Loss) on Investments	40,517	$ 29,335	(13,796)	864
Warrant [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	2,600		2,600
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	(2,601)		(2,601)
Other Investments [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	20		20
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	(16)		(16)
Equity Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net	$ 0		0
Fair Value, Inputs, Level 3 [Member] | Warrant [Member]
Unrealized Gain (Loss) on Investments			600	300
Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member]
Unrealized Gain (Loss) on Investments			10,100	6,000
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Unrealized Gain (Loss) on Investments			$ 9,700	$ 4,500
The 2026 Notes [Member]
Debt Instrument, Share Price (in dollars per share) | $ / shares	$ 24.9		$ 24.9
The 2026 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Debt Instrument, Fair Value Disclosure	$ 57,300		$ 57,300
The 2027 Notes [Member]
Debt Instrument, Share Price (in dollars per share) | $ / shares	$ 24.71		$ 24.71
The 2027 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Debt Instrument, Fair Value Disclosure	$ 56,800		$ 56,800
The 2031 Convertible Notes [Member]
Debt Instrument, Fair Value Disclosure	2,700		2,700
The 2030 Convertible Notes [Member]
Debt Instrument, Fair Value Disclosure	$ 39,900		$ 39,900
Measurement Input, Hypothetical Market Yields [Member]
Debt Instrument, Measurement Input					0.25

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