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v3.25.1

Portfolio Company Investments - Schedule of Consolidated Schedule of Investments in and Advances to Affiliates (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Fair Value, beginning balance | [1],[2],[3],[4] | $ 1,090,506 |  |  |  |
Fair Value, ending balance |  | 1,154,408 | [5],[6],[7],[8] |  | $ 1,090,506 | [1],[2],[3],[4]
Net Change in Unrealized Appreciation (Depreciation) |  | (9,793) |  | $ 1,218 |  |
Control Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Principal Amount - Debt Investments |  | 5,226 |  |  | 5,226 |
Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Principal Amount - Debt Investments |  | 30,952 |  |  | 32,461 |
Fair Value, beginning balance |  | 102,024 |  | 83,876 | 83,876 |
Gross Additions |  | 12,246 |  |  | 21,441 |
Gross Reductions |  | (23,204) |  |  | (3,293) |
Fair Value, ending balance |  | 91,066 |  |  | 102,024 |
Net Realized Gain (Losses) |  | 10,066 |  |  |  |
Net Change in Unrealized Appreciation (Depreciation) |  | (6,890) |  |  | 7,954 |
Interest Income |  | 1,094 |  |  | 3,533 |
Payment-in-kind Interest Income |  |  |  |  | 9 |
Dividend Income |  | 886 |  |  | 1,830 |
Fee Income |  | 8 |  |  | 183 |
US GreenFiber, LLC | Control Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Principal Amount - Debt Investments |  | 5,226 |  |  | 5,226 |
Applegate Greenfiber Intermediate Inc. (fka US GreenFiber, LLC) | Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Principal Amount - Debt Investments |  | 9,602 |  |  | 9,602 |
Fair Value, beginning balance |  | 24,387 |  | 24,590 | 24,590 |
Gross Reductions |  | (1,278) |  |  | (203) |
Fair Value, ending balance |  | 23,109 |  |  | 24,387 |
Net Change in Unrealized Appreciation (Depreciation) |  | (1,278) |  |  | (202) |
Interest Income |  | 264 |  |  | 1,074 |
CP Communications, LLC | Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Principal Amount - Debt Investments |  | 6,350 |  |  | 7,859 |
Fair Value, beginning balance |  | 8,306 |  |  |  |
Gross Additions |  | 10 |  |  | 8,360 |
Gross Reductions |  | (1,510) |  |  | (54) |
Fair Value, ending balance |  | 6,806 |  |  | 8,306 |
Interest Income |  | 285 |  |  | 88 |
Payment-in-kind Interest Income |  |  |  |  | 9 |
Fee Income |  | 3 |  |  | 163 |
Medsurant Holdings, LLC | Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Fair Value, beginning balance |  | 9,863 |  | 5,930 | 5,930 |
Gross Additions |  | 10,066 |  |  | 4,262 |
Gross Reductions |  | (19,558) |  |  | (329) |
Fair Value, ending balance |  | 371 |  |  | 9,863 |
Net Realized Gain (Losses) |  | 10,066 |  |  |  |
Net Change in Unrealized Appreciation (Depreciation) |  | (6,918) |  |  | 4,261 |
Dividend Income |  | 538 |  |  | 1,328 |
Pfanstiehl, Inc | Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Fair Value, beginning balance |  | 39,923 |  | 33,321 | 33,321 |
Gross Additions |  | 2,165 |  |  | 6,602 |
Fair Value, ending balance |  | 42,088 |  |  | 39,923 |
Net Change in Unrealized Appreciation (Depreciation) |  | 2,165 |  |  | 6,602 |
Dividend Income |  | 348 |  |  | 348 |
Spectra A&D Acquisition, Inc. (fka FDS Avionics Corp.) | Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Principal Amount - Debt Investments |  | 15,000 |  |  | 15,000 |
Fair Value, beginning balance |  | 14,921 |  | 15,321 | 15,321 |
Gross Additions |  | 5 |  |  | 2,217 |
Gross Reductions |  | (393) |  |  | (2,617) |
Fair Value, ending balance |  | 14,533 |  |  | 14,921 |
Net Change in Unrealized Appreciation (Depreciation) |  | (394) |  |  | (2,617) |
Interest Income |  | 545 |  |  | 2,371 |
Fee Income |  | 5 |  |  | 20 |
Steward Holding LLC (dba Steward Advanced Materials) | Affiliate Investments |  |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |  |
Fair Value, beginning balance |  | 4,624 |  | $ 4,714 | 4,714 |
Gross Reductions |  | (465) |  |  | (90) |
Fair Value, ending balance |  | 4,159 |  |  | 4,624 |
Net Change in Unrealized Appreciation (Depreciation) |  | $ (465) |  |  | (90) |
Dividend Income |  |  |  |  | $ 154 |
[1] | (a) See Note 3 to the consolidated financial statements for portfolio composition by geographic location.
[2] | (b) Equity ownership may be held in shares or units of companies related to the portfolio companies. The Company’s investments are generally classified as “restricted securities”, unless otherwise noted, as such term is defined under Regulation S-X Rule 6-03(f) or Securities Act Rule 144. As of December 31, 2024, the Company held restricted securities with an aggregate fair value of $1,090,506, or 166% of the Company's net assets.
[3] | (c) All debt investments are income producing, unless otherwise indicated. Equity investments are non-income producing unless otherwise noted.
[4] | (g) Except as otherwise noted, the Company’s investment portfolio is comprised of debt and equity securities of privately held companies for which quoted prices falling within the categories of Level 1 and Level 2 inputs are not available. Therefore, the Company values all of its portfolio investments at fair value, as determined in good faith by the board of directors, using significant unobservable Level 3 inputs.
[5] | All debt investments are income producing, unless otherwise indicated. Equity investments are non-income producing unless otherwise noted.
[6] | Equity ownership may be held in shares or units of companies related to the portfolio companies. The Company’s investments are generally classified as “restricted securities”, unless otherwise noted, as such term is defined under Regulation S-X Rule 6-03(f) or Securities Act Rule 144. As of March 31, 2025, the Company held restricted securities with an aggregate fair value of $1,154,408, or 170% of the Company's net assets.
[7] | Except as otherwise noted, the Company’s investment portfolio is comprised of debt and equity securities of privately held companies for which quoted prices falling within the categories of Level 1 and Level 2 inputs are not available. Therefore, the Company values all of its portfolio investments at fair value, as determined in good faith by the board of directors, using significant unobservable Level 3 inputs.
[8] | See Note 3 to the consolidated financial statements for portfolio composition by geographic location.

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