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Note 5 - Transactions With Affiliated Companies - Investments in Affiliated Companies (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023
Investments, fair value |  |  | $ 709,085 |
Net unrealized appreciation (depreciation) on investments | $ (24,511) | $ 608 | (28,471) | $ (6,929)
Net realized gain (loss) on investments | 2,464 | (16,529) | 2,472 | (16,697)
Investments, fair value | 646,862 |  | 646,862 |
Interest Income, Operating, Paid in Kind |  |  | 1,737 | 2,154
Investment, Affiliated Issuer, Noncontrolled [Member] |  |  |  |
Investments, fair value | 12,577 | 846 | 1,132 | 0
Purchases | 92 | 0 | 107 | 0
Reductions | (40) | 0 | (40) | 0
Transfers in/(out) at fair value | 0 | 0 | 0 | 0
Discount accretion | 0 | 0 | 0 | 0
Net unrealized appreciation (depreciation) on investments | 3,178 | 60 | 14,611 | 906
Net realized gain (loss) on investments | 40 | 0 | 37 | 0
Investments, fair value | 15,847 | 906 | 15,847 | 906
Investment, Affiliated Issuer, Noncontrolled [Member] | Aulea Medical, Inc. [Member] |  |  |  |
Investments, fair value | 0 |  | 0 |
Purchases | 0 |  | 3 |
Reductions | (40) |  | (40) |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 0 |  | 0 |
Net realized gain (loss) on investments | 40 |  | 37 |
Investments, fair value | 0 |  | 0 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Cadrenal Therapeutics, Inc. [Member] |  |  |  |
Investments, fair value |  | 846 |  | 0
Purchases |  | 0 |  | 0
Reductions |  | 0 |  | 0
Transfers in/(out) at fair value |  | 0 |  | 0
Discount accretion |  | 0 |  | 0
Net unrealized appreciation (depreciation) on investments |  | 60 |  | 906
Net realized gain (loss) on investments |  | 0 |  | 0
Investments, fair value |  | 906 |  | 906
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment One [Member] |  |  |  |
Investments, fair value | 2,790 |  | 222 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 713 |  | 3,281 |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 3,503 |  | 3,503 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment Two [Member] |  |  |  |
Investments, fair value | 4,207 |  | 336 |
Purchases | 92 |  | 104 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 1,041 |  | 4,900 |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 5,340 |  | 5,340 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment Three [Member] |  |  |  |
Investments, fair value | 1,674 |  | 133 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 427 |  | 1,968 |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 2,101 |  | 2,101 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment Four [Member] |  |  |  |
Investments, fair value | 1,674 |  | 133 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 427 |  | 1,968 |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 2,101 |  | 2,101 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment Five [Member] |  |  |  |
Investments, fair value | 1,116 |  | 88 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 285 |  | 1,313 |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 1,401 |  | 1,401 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment Six [Member] |  |  |  |
Investments, fair value | 1,116 |  | 88 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | 285 |  | 1,313 |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 1,401 |  | 1,401 |
Investment, Affiliated Issuer, Noncontrolled [Member] | Evelo Biosciences, Inc. [Member] | Investment Seven [Member] |  |  |  |
Investments, fair value |  |  | 132 |
Purchases |  |  | 0 |
Reductions |  |  | 0 |
Transfers in/(out) at fair value |  |  | 0 |
Discount accretion |  |  | 0 |
Net unrealized appreciation (depreciation) on investments |  |  | (132) |
Net realized gain (loss) on investments |  |  | 0 |
Investments, fair value | 0 |  | 0 |
Investment, Affiliated Issuer, Controlled [Member] |  |  |  |
Investments, fair value | 13,644 |  | 14,223 |
Purchases | 1,500 |  | 2,477 |
Reductions | 0 |  | (547) |
Transfers in/(out) at fair value | 463 |  | 463 |
Discount accretion | 3 |  | 7 |
Net unrealized appreciation (depreciation) on investments | (4,402) | 0 | (5,581) | 0
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 11,386 |  | 11,386 |
Interest Income, Operating, Paid in Kind | 178 |  | 344 |
Interest income | 188 | $ 0 | 365 | $ 0
Investment, Affiliated Issuer, Controlled [Member] | Investment [Member] |  |  |  |
Interest income | 188 |  | 365 |
Investment, Affiliated Issuer, Controlled [Member] | Better Place Forests Co. [Member] | Investment One [Member] |  |  |  |
Investments, fair value | 3,455 |  | 3,339 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 2 |  | 4 |
Net unrealized appreciation (depreciation) on investments | (406) |  | (403) |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 3,166 |  | 3,166 |
Interest Income, Operating, Paid in Kind | 115 |  | 226 |
Interest income | 120 |  | 236 |
Investment, Affiliated Issuer, Controlled [Member] | Better Place Forests Co. [Member] | Investment Two [Member] |  |  |  |
Investments, fair value | 1,688 |  | 1,630 |
Purchases | 0 |  | 0 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 1 |  | 3 |
Net unrealized appreciation (depreciation) on investments | (197) |  | (196) |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 1,549 |  | 1,549 |
Interest Income, Operating, Paid in Kind | 57 |  | 112 |
Interest income | 62 |  | 123 |
Investment, Affiliated Issuer, Controlled [Member] | Better Place Forests Co. [Member] | Investment Three [Member] |  |  |  |
Investments, fair value | 0 |  | 0 |
Purchases | 500 |  | 500 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | (85) |  | (85) |
Net realized gain (loss) on investments | 0 |  |  |
Investments, fair value | 420 |  | 420 |
Interest Income, Operating, Paid in Kind | 5 |  | 5 |
Interest income | 5 |  | 5 |
Investment, Affiliated Issuer, Controlled [Member] | Better Place Forests Co. [Member] | Investment Four [Member] |  |  |  |
Investments, fair value | 0 |  | 0 |
Purchases | 500 |  | 500 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | (86) |  | (86) |
Net realized gain (loss) on investments | 0 |  |  |
Investments, fair value | 415 |  | 415 |
Interest Income, Operating, Paid in Kind | 1 |  | 1 |
Interest income | 1 |  | 1 |
Investment, Affiliated Issuer, Controlled [Member] | Better Place Forests Co. [Member] | Investment Five [Member] |  |  |  |
Investments, fair value | 2,656 |  | 3,024 |
Purchases | 500 |  | 1,250 |
Reductions | 0 |  | 0 |
Transfers in/(out) at fair value | 0 |  | 0 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | (3,156) |  | (4,274) |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 0 |  | 0 |
Interest Income, Operating, Paid in Kind | 0 |  | 0 |
Interest income | 0 |  | 0 |
Investment, Affiliated Issuer, Controlled [Member] | HIMV LLC [Member] |  |  |  |
Investments, fair value | 5,845 |  | 6,230 |
Purchases | 0 |  | 227 |
Reductions | 0 |  | (547) |
Transfers in/(out) at fair value | 463 |  | 463 |
Discount accretion | 0 |  | 0 |
Net unrealized appreciation (depreciation) on investments | (472) |  | (537) |
Net realized gain (loss) on investments | 0 |  | 0 |
Investments, fair value | 5,836 |  | 5,836 |
Interest Income, Operating, Paid in Kind | 0 |  | 0 |
Interest income | $ 0 |  | $ 0 |

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