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v3.23.1

Note 5 - Transactions With Affiliated Companies - Investments in Affiliated Companies (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Investments, fair value | $ 720,026 |
Unrealized Gain (Loss) on Investments | (7,537) | $ (2,237)
Net realized gain (loss) on investments | (168) | 30
Investments, fair value | 715,312 |
Investment, Affiliated Issuer, Noncontrolled [Member] |  |
Investments, fair value | 0 |
Purchases | 0 |
Principal payments | 0 |
Transfers in/(out) at fair value | 0 |
Discount accretion | 0 |
Unrealized Gain (Loss) on Investments | 846 | 0
Net realized gain (loss) on investments | 0 |
Investments, fair value | 846 |
Interest income | 0 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Cadrenal Therapeutics, Inc. [Member] |  |
Investments, fair value | 0 |
Purchases | 0 |
Principal payments | 0 |
Transfers in/(out) at fair value | 0 |
Discount accretion | 0 |
Unrealized Gain (Loss) on Investments | 846 |
Net realized gain (loss) on investments | 0 |
Investments, fair value | 846 |
Interest income | 0 |
Investment, Affiliated Issuer, Controlled [Member] |  |
Investments, fair value |  | 0
Purchases |  | 0
Principal payments |  | (50)
Transfers in/(out) at fair value |  | 0
Discount accretion |  | 0
Unrealized Gain (Loss) on Investments | $ 0 | 50
Net realized gain (loss) on investments |  | 0
Investments, fair value |  | 0
Interest income |  | 0
Investment, Affiliated Issuer, Controlled [Member] | HESP LLC [Member] |  |
Investments, fair value |  | 0
Purchases |  | 0
Principal payments |  | (50)
Transfers in/(out) at fair value |  | 0
Discount accretion |  | 0
Unrealized Gain (Loss) on Investments |  | 50
Net realized gain (loss) on investments |  | 0
Investments, fair value |  | 0
Interest income |  | $ 0

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