| Investments in and Advances to Affiliates, Schedule of Investments [Text Block] |
Note 5. Transactions with affiliated companies
A non-controlled affiliated company is generally a portfolio company in which the Company owns 5% or more of such portfolio company’s voting securities but not more than 25% of such portfolio company’s voting securities.
Transactions related to investments in non-controlled affiliated companies for the three months ended March 31, 2026 were as follows:
| | | | | | | | | | | Three months ended March 31, 2026 | | | | | | | | | | | | | |
| | | Fair value at | | | | | | | | | | | | | | | Transfers | | | | | | | Net | | | | | | | Fair value at | | | | | |
| Portfolio | | December 31, | | | | | | | Principal | | | | | | | in/(out) at | | | Discount | | | unrealized | | | Net realized | | | March 31, | | | Interest | |
| Company | | 2025 | | | Purchases | | | payments | | | PIK | | | fair value | | | accretion | | | gain/(loss) | | | gain/(loss) | | | 2026 | | | income | |
| | | (In thousands) | |
| Aulea Medical, Inc. | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | | | | | $ | — | | | $ | — | |
| Evelo Biosciences, Inc. | | | 1,486 | | | | — | | | | — | | | | — | | | | — | | | | — | | | | | | | | — | | | | 1,486 | | | | — | |
| Hound Labs II LLC | | | 11,369 | | | | — | | | | — | | | | 219 | | | | — | | | | — | | | | (15 | ) | | | — | | | | 11,573 | | | | 219 | |
| Nexii, Inc. | | | — | | | | 4 | | | | — | | | | — | | | | — | | | | — | | | | (4 | ) | | | — | | | | — | | | | 27 | |
| NextCar Holding Company, Inc. | | | 1,079 | | | | — | | | | (243 | ) | | | — | | | | — | | | | — | | | | 169 | | | | — | | | | 1,005 | | | | 55 | |
| Shengrow Inc. | | | 49,210 | | | | — | | | | — | | | | 622 | | | | — | | | | 306 | | | | — | | | | — | | | | 50,138 | | | | 1,271 | |
| Total non-controlled affiliates | | $ | 63,144 | | | $ | 4 | | | $ | (243 | ) | | $ | 841 | | | $ | — | | | $ | 306 | | | $ | 150 | | | $ | — | | | $ | 64,202 | | | $ | 1,572 | |
Transactions related to investments in non-controlled affiliated companies for the three months ended March 31, 2025 were as follows:
| | | | | | | | | | | Three months ended March 31, 2025 | | | | | | | | | | | | | |
| | | Fair value at | | | | | | | | | | | | | | Transfers | | | | | | | Net | | | | | | | Fair value at | | | | | |
| Portfolio | | December 31, | | | | | | | | | | | | | | in/(out) at | | | Discount | | | unrealized | | | Net realized | | | March 31, | | | Interest | |
| Company | | 2024 | | | Purchases | | | Sales | | | PIK | | | fair value | | | accretion | | | gain/(loss) | | | gain/(loss) | | | 2025 | | | income | |
| | | (In thousands) | |
| Aulea Medical, Inc. | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | — | |
| Evelo Biosciences, Inc. | | | 8,307 | | | | 2 | | | | — | | | | — | | | | — | | | | — | | | | (2 | ) | | | — | | | | 8,307 | | | | — | |
| Total non-controlled affiliates | | $ | 8,307 | | | $ | 2 | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | (2 | ) | | $ | — | | | $ | 8,307 | | | $ | — | |
A controlled affiliated company is generally a portfolio company in which the Company owns more than 25% of such portfolio company’s voting securities or has the power to exercise control over management or policies of such portfolio company (including through a management agreement).
There were no transactions related to investments in controlled affiliated companies for the three months ended March 31, 2026.
Transactions related to investments in controlled affiliated companies for the three months ended March 31, 2025 were as follows:
| | | | | | | | | | | Three months ended March 31, 2025 | | | | | | | | | | | | | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| | | Fair value at | | | | | | | | | | | | Transfers | | | | | | Net | | | | | | Fair value at | | | Interest | |
| Portfolio | | December 31, | | | | | | | Principal | | | | | | | in/(out) at | | | Discount | | | unrealized | | | Net realized | | | March 31, | | | income | |
| Company | | 2024 | | | Purchases | | | payments | | | PIK | | | fair value | | | accretion | | | gain/(loss) | | | gain/(loss) | | | 2025 | | | (reversal) | |
| | | (In thousands) | |
| Better Place Forests Co. | | $ | — | | | $ | 941 | | | $ | — | | | $ | — | | | $ | — | | | $ | — | | | $ | (62 | ) | | $ | — | | | $ | 879 | | | $ | — | |
| HIMV LLC | | | 6,230 | | | | — | | | | — | | | | — | | | | — | | | | — | | | | (940 | ) | | | — | | | | 5,290 | | | | — | |
| Nexii, Inc. | | | 8,547 | | | | — | | | | — | | | | — | | | | — | | | | — | | | | 153 | | | | — | | | | 8,700 | | | | 20 | |
| Swift Health Systems, Inc. | | | 17,042 | | | | 2,009 | | | | — | | | | 208 | | | | — | | | | 9 | | | | (19,268 | ) | | | — | | | | — | | | | (81 | ) |
| Total controlled affiliates | | $ | 31,819 | | | $ | 2,950 | | | $ | — | | | $ | 208 | | | $ | — | | | $ | 9 | | | $ | (20,117 | ) | | $ | — | | | $ | 14,869 | | | $ | (61 | ) |
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