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Note 6 - Fair Value (Details Textual) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($) $ / shares	Mar. 31, 2023 USD ($)	Jun. 30, 2022
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	$ 0
Unrealized Gain (Loss) on Investments	(3,960)	$ (7,537)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers, Net		0
Fair Value, Inputs, Level 1 [Member] | Warrants and Equity Securities [Member]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0
Fair Value, Inputs, Level 3 [Member] | Debt Securities [Member]
Unrealized Gain (Loss) on Investments	(1,800)	(4,600)
Fair Value, Inputs, Level 3 [Member] | Equity Securities [Member]
Unrealized Gain (Loss) on Investments	$ (1,200)	(200)
Fair Value, Inputs, Level 3 [Member] | Warrant [Member]
Unrealized Gain (Loss) on Investments		$ (1,400)
The 2026 Notes [Member]
Debt Instrument, Share Price (in dollars per share) | $ / shares	$ 23.75
The 2026 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Debt Instrument, Fair Value Disclosure	$ 54,600
The 2027 Notes [Member]
Debt Instrument, Share Price (in dollars per share) | $ / shares	$ 23.8
The 2027 Notes [Member] | Fair Value, Inputs, Level 1 [Member]
Debt Instrument, Fair Value Disclosure	$ 54,700
Asset-backed Notes 2022 [Member] | Fair Value, Inputs, Level 3 [Member]
Debt Instrument, Fair Value Disclosure	$ 100,000
Measurement Input, Hypothetical Market Yields [Member]
Debt Instrument, Measurement Input			0.25

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