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v3.23.3

Financial Highlights (Details) $ / shares in Units, € in Thousands, £ in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2023 USD ($) $ / shares shares | Sep. 30, 2022 USD ($) $ / shares shares | Sep. 30, 2023 USD ($) $ / shares shares | Sep. 30, 2022 USD ($) $ / shares shares | Sep. 30, 2023 GBP (£) shares | Sep. 30, 2023 EUR (€) shares | Dec. 31, 2022 USD ($) shares | Dec. 31, 2022 GBP (£) shares | Dec. 31, 2022 EUR (€) shares | Sep. 30, 2022 GBP (£) shares | Sep. 30, 2022 EUR (€) shares
Investment Company, Financial Highlights [Roll Forward] |  |  |  |  |  |  |  |  |  |  |
Net asset value, beginning balance (in dollars per share) | $ / shares |  |  | $ 13.02 | $ 13.49 |  |  |  |  |  |  |
Net investment income (in dollars per share) | $ / shares |  |  | 1.17 | 0.94 |  |  |  |  |  |  |
Net realized and unrealized losses (in dollars per share) | $ / shares |  |  | (0.10) | (0.33) |  |  |  |  |  |  |
Total net increase (in dollars per share) | $ / shares |  |  | 1.07 | 0.61 |  |  |  |  |  |  |
Distributions declared to stockholders from net investment income (in dollars per share) | $ / shares |  |  | (1.03) | (0.90) |  |  |  |  |  |  |
Net asset value, ending balance (in dollars per share) | $ / shares | $ 13.06 | $ 13.20 | 13.06 | 13.20 |  |  |  |  |  |  |
Per share market value (in dollars per share) | $ / shares | $ 12.95 | $ 11.53 | $ 12.95 | $ 11.53 |  |  |  |  |  |  |
Total return based on market value |  |  | 13.49% | (9.64%) |  |  |  |  |  |  |
Total return based on net asset value |  |  | 8.39% | 4.54% |  |  |  |  |  |  |
Shares outstanding at end of period (in shares) | shares | 101,439,649 |  | 101,439,649 |  | 101,439,649 | 101,439,649 | 100,937,026 | 100,937,026 | 100,937,026 | 100,937,026 | 100,937,026
Average weighted shares outstanding for the period - basic (in shares) | shares | 100,954,898 | 100,830,075 | 100,943,049 | 99,955,432 |  |  |  |  |  |  |
Average net assets for the period |  |  | $ 1,322,558 | $ 1,348,479 |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  | 11.95% | 9.27% |  |  |  |  |  |  |
Total expenses, before waivers/reimbursements |  |  | 16.77% | 12.85% |  |  |  |  |  |  |
Total expenses, net of waivers/reimbursements |  |  | 16.45% | 12.50% |  |  |  |  |  |  |
Asset coverage ratio | 182.68% |  | 182.68% |  | 182.68% | 182.68% |  |  |  | 179.28% | 179.28%
Portfolio turnover |  |  | 4.36% | 14.38% |  |  |  |  |  |  |
Accretion effect (in dollars per share) | $ / shares | $ 0.00 | $ 0.01 | $ 0.00 | $ 0.01 |  |  |  |  |  |  |
Unsecured Notes |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | $ 391,500 | $ 539,870 | $ 433,661 | $ 525,456 |  |  |  |  |  |  |
SBA-guaranteed debentures |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 300,000 | 300,000 | 300,000 | 300,000 |  |  |  |  |  |  |
Convertible Notes |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 317,138 | 201,250 | 340,881 | 201,250 |  |  |  |  |  |  |
Holdings Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 569,563 |  | 569,563 |  |  |  | $ 618,963 |  |  |  |
Holdings Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 569,563 |  | 569,563 |  |  |  | 618,963 |  |  |  |
Holdings Credit Facility | Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 563,470 | 607,585 | 603,154 | 580,699 |  |  |  |  |  |  |
DB Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 186,400 |  | 186,400 |  |  |  | 186,400 |  |  |  |
DB Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 186,400 |  | 186,400 |  |  |  | 186,400 |  |  |  |
DB Credit Facility | Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 186,487 | 199,442 | 186,429 | 217,817 |  |  |  |  |  |  |
NMFC Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 192,115 |  | 192,115 |  |  |  | 40,359 |  |  |  |
NMFC Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 192,115 |  | 192,115 |  | £ 22,850 | € 700 | 40,359 | £ 22,850 | € 700 | £ 22,850 | € 700
NMFC Credit Facility | Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | 141,764 | 171,850 | 104,227 | 156,303 |  |  |  |  |  |  |
NMNLC Credit Facility II |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 2,858 |  | 2,858 |  |  |  | 3,785 |  |  |  |
NMNLC Credit Facility II | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Credit facility outstanding balance | 2,858 |  | 2,858 |  |  |  | $ 3,785 |  |  |  |
NMNLC Credit Facility II | Credit Facility | Revolving Credit Facility |  |  |  |  |  |  |  |  |  |  |
Ratio to average net assets: |  |  |  |  |  |  |  |  |  |  |
Average debt outstanding | $ 2,091 | $ 2,013 | $ 2,480 | $ 8,939 |  |  |  |  |  |  |

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