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Note 6 - Fair Value - Assets at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands | Jun. 30, 2026 | Dec. 31, 2025
--- | --- | ---
Fair Value, Recurring [Member] |  |  |
Investments, fair value |  | $ 676,711 | $ 647,244
Fair Value, Recurring [Member] | Debt [Member] |  |  |
Investments, fair value |  | 647,999 | 596,025
Fair Value, Recurring [Member] | Warrant [Member] |  |  |
Investments, fair value |  | 16,703 | 16,648
Fair Value, Recurring [Member] | Other Investment [Member] |  |  |
Investments, fair value |  | 4,037 | 3,444
Fair Value, Recurring [Member] | Equity Securities [Member] |  |  |
Investments, fair value |  | 7,757 | 31,127
Fair Value, Recurring [Member] | Joint Venture Investment Funds [Member] |  |  |
Investments, fair value | [1] | 215 |
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] |  |  |
Investments, fair value |  | 1,875 | 3,988
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Debt [Member] |  |  |
Investments, fair value |  | 0 | 0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Warrant [Member] |  |  |
Investments, fair value |  | 0 | 0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Other Investment [Member] |  |  |
Investments, fair value |  | 0 | 0
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Equity Securities [Member] |  |  |
Investments, fair value |  | 1,875 | 3,988
Fair Value, Inputs, Level 1 [Member] | Fair Value, Recurring [Member] | Joint Venture Investment Funds [Member] |  |  |
Investments, fair value | [1] | 0 |
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] |  |  |
Investments, fair value |  | 2,590 | 1,916
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Debt [Member] |  |  |
Investments, fair value |  | 0 | 0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Warrant [Member] |  |  |
Investments, fair value |  | 2,590 | 1,916
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Other Investment [Member] |  |  |
Investments, fair value |  | 0 | 0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Equity Securities [Member] |  |  |
Investments, fair value |  | 0 | 0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Recurring [Member] | Joint Venture Investment Funds [Member] |  |  |
Investments, fair value | [1] | 0 |
Fair Value, Inputs, Level 3 [Member] |  |  |
Investments, fair value |  | 672,031 | 641,340
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] |  |  |
Investments, fair value |  | 672,031 | 641,340
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Debt [Member] |  |  |
Investments, fair value |  | 647,999 | 596,025
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Warrant [Member] |  |  |
Investments, fair value |  | 14,113 | 14,732
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Other Investment [Member] |  |  |
Investments, fair value |  | 4,037 | 3,444
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Equity Securities [Member] |  |  |
Investments, fair value |  | 5,882 | $ 27,139
Fair Value, Inputs, Level 3 [Member] | Fair Value, Recurring [Member] | Joint Venture Investment Funds [Member] |  |  |
Investments, fair value | [1] | $ 0 |
[1] | The fair value of the Company's investment in the RoHo Joint Venture is determined using the net asset value of the Company's ownership interest in member's capital.

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