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v3.25.3

Financial Highlights (Details) $ / shares in Units, € in Thousands, £ in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2025 USD ($) $ / shares shares | Sep. 30, 2024 USD ($) $ / shares | Sep. 30, 2025 USD ($) $ / shares shares | Sep. 30, 2024 USD ($) $ / shares shares | Sep. 30, 2025 EUR (€) shares | Sep. 30, 2025 GBP (£) shares | Dec. 31, 2024 USD ($) shares | Dec. 31, 2024 EUR (€) shares | Dec. 31, 2024 GBP (£) shares | Sep. 30, 2024 EUR (€) shares | Sep. 30, 2024 GBP (£) shares
Investment Company, Financial Highlights [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Net asset value, beginning balance (in dollars per share) | $ / shares |  |  | $ 12.55 | $ 12.87 |  |  |  |  |  |  |
Net investment income (in dollars per share) | $ / shares |  |  | 0.96 | 1.05 |  |  |  |  |  |  |
Net realized and unrealized losses (in dollars per share) | $ / shares |  |  | (0.56) | (0.26) |  |  |  |  |  |  |
Total net increase (in dollars per share) | $ / shares |  |  | 0.40 | 0.79 |  |  |  |  |  |  |
Repurchase of common stock (in dollars per share) | $ / shares |  |  | 0.07 | 0 |  |  |  |  |  |  |
Distributions declared to stockholders from net investment income (in dollars per share) | $ / shares |  |  | (0.96) | (1.04) |  |  |  |  |  |  |
Net asset value, ending balance (in dollars per share) | $ / shares | $ 12.06 | $ 12.62 | 12.06 | 12.62 |  |  |  |  |  |  |
Per share market value (in dollars per share) | $ / shares | $ 9.64 | $ 11.98 | $ 9.64 | $ 11.98 |  |  |  |  |  |  |
Total return based on market value |  |  | (6.24%) | 2.40% |  |  |  |  |  |  |
Total return based on net asset value |  |  | 3.86% | 6.32% |  |  |  |  |  |  |
Shares outstanding at end of period (in shares) | shares | 104,189,336 |  | 104,189,336 |  | 104,189,336 | 104,189,336 | 107,851,415 | 107,851,415 | 107,851,415 | 107,851,415 | 107,851,415
Average weighted shares outstanding for the period (in shares) | shares |  |  | 107,199,318 | 106,140,789 |  |  |  |  |  |  |
Average net assets for the period |  |  | $ 1,329,882 | $ 1,357,569 |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  | 10.35% | 10.93% |  |  |  |  |  |  |
Total expenses, before waivers/reimbursements |  |  | 15.62% | 16.90% |  |  |  |  |  |  |
Total expenses, net of waivers/reimbursements |  |  | 14.72% | 16.63% |  |  |  |  |  |  |
Asset coverage ratio | 179.09% |  | 179.09% |  | 179.09% | 179.09% |  |  |  | 179.18% | 179.18%
Portfolio turnover |  |  | 12.18% | 17.99% |  |  |  |  |  |  |
Accretive effect of common stock issuances per share (in dollars per share) | $ / shares |  |  | $ 0.00 | $ (0.02) |  |  |  |  |  |  |
Holdings Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | $ 308,063 |  | $ 308,063 |  |  |  | $ 294,363 |  |  |  |
NMFC Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 31,032 |  | 31,032 |  |  |  | 27,944 |  |  |  |
Revolving Credit Facility | Holdings Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 308,063 |  | 308,063 |  |  |  | 294,363 |  |  |  |
Revolving Credit Facility | NMFC Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 31,032 |  | 31,032 |  | € 16,512 | £ 8,666 | $ 27,944 | € 16,512 | £ 8,666 | € 17,400 | £ 26,650
Unsecured Notes |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 990,000 | $ 706,304 | 990,000 | $ 676,414 |  |  |  |  |  |  |
Line of Credit | Revolving Credit Facility | Holdings Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 293,932 | 405,661 | 285,184 | 364,418 |  |  |  |  |  |  |
Line of Credit | Revolving Credit Facility | NMFC Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 30,991 | 140,385 | 29,879 | 79,969 |  |  |  |  |  |  |
Line of Credit | Revolving Credit Facility | DB Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding |  | 180,022 | 0 | 182,364 |  |  |  |  |  |  |
Line of Credit | Revolving Credit Facility | NMNLC Credit Facility II |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding |  | 2,151 | 0 | 2,341 |  |  |  |  |  |  |
SBA-guaranteed debentures |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 240,882 | 300,000 | 263,319 | 300,000 |  |  |  |  |  |  |
2022 Convertible Notes |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | $ 258,777 | $ 260,000 | $ 259,022 | $ 260,000 |  |  |  |  |  |  |

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