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v3.25.2

Net Assets - Roll Forward of Net Assets (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 113 Months Ended
--- | --- | --- | ---
Jun. 30, 2025 | Mar. 31, 2025 | Jun. 30, 2024 | Mar. 31, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | $ 1,348,178 | $ 1,359,291 | $ 1,369,183 | $ 1,331,723 | $ 1,359,291 | $ 1,331,723 |
Issuances of common stock |  |  | $ 19,772 | 47,919 |  |  |
Shares repurchased under repurchase program (in shares) | (925,216) |  | 0 |  | (925,216) | 0 |
Repurchases of common stock | $ (9,642) |  |  |  | $ (9,642) |  | $ (12,590)
Conversion of 2022 Convertible Notes (in shares) | 514 |  | 0 |  | 514 | 0 |
Offering costs |  | (28) | $ (388) | (81) |  |  |
Offering costs | $ 14 |  |  |  |  |  |
Distributions declared | (34,589) | (34,602) | (36,834) | (38,462) |  |  |
Net increase (decrease) in net assets resulting from operations | 7,875 | 23,517 | 34,784 | 28,084 | $ 31,392 | $ 62,868 |
Ending of the period | 1,311,836 | 1,348,178 | 1,386,517 | 1,369,183 | 1,311,836 | 1,386,517 | 1,311,836
Total Net Assets of NMFC |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | 1,342,212 | 1,353,339 | 1,356,932 | 1,319,951 | 1,353,339 | 1,319,951 |
Issuances of common stock |  |  | 19,772 | 47,919 |  |  |
Repurchases of common stock | (9,642) |  | 0 |  | (9,642) | 0 |
Offering costs | 14 | (28) | (388) | (81) | (14) | (469) |
Offering costs | 14 |  |  |  |  |  |
Distributions declared | (34,499) | (34,512) | (36,669) | (38,265) | (69,011) | (74,934) |
Net increase (decrease) in net assets resulting from operations | 7,774 | 23,413 | 34,471 | 27,408 | 31,187 | 61,879 |
Ending of the period | $ 1,305,859 | $ 1,342,212 | $ 1,374,118 | $ 1,356,932 | $ 1,305,859 | $ 1,374,118 | $ 1,305,859
Common Stock |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Shares outstanding, beginning of the period (in shares) | 107,851,415 | 107,851,415 | 106,289,293 | 102,558,859 | 107,851,415 | 102,558,859 |
Beginning of the period | $ 1,079 | $ 1,079 | $ 1,063 | $ 1,026 | $ 1,079 | $ 1,026 |
Issuances of common stock (in shares) |  |  | 1,562,122 | 3,730,434 |  |  |
Issuances of common stock |  |  | $ 16 | $ 37 |  |  |
Shares repurchased under repurchase program (in shares) | (925,216) |  |  |  |  |  |
Conversion of 2022 Convertible Notes (in shares) | 514 |  |  |  |  |  |
Shares outstanding, ending of the period (in shares) | 106,926,713 | 107,851,415 | 107,851,415 | 106,289,293 | 106,926,713 | 107,851,415 | 106,926,713
Ending of the period | $ 1,079 | $ 1,079 | $ 1,079 | $ 1,063 | $ 1,079 | $ 1,079 | $ 1,079
Treasury Stock at Cost |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | 0 | 0 |  |  | 0 |  |
Repurchases of common stock | (9,642) |  |  |  |  |  |
Ending of the period | (9,642) | 0 |  |  | (9,642) |  | (9,642)
Paid in Capital in Excess of Par |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | 1,365,824 | 1,365,852 | 1,379,070 | 1,331,269 | 1,365,852 | 1,331,269 |
Issuances of common stock |  |  | 19,756 | 47,882 |  |  |
Offering costs |  | (28) | (388) | (81) |  |  |
Offering costs | 14 |  |  |  |  |  |
Ending of the period | 1,365,838 | 1,365,824 | 1,398,438 | 1,379,070 | 1,365,838 | 1,398,438 | 1,365,838
Accumulated Net Investment Income |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | 181,278 | 181,266 | 149,467 | 150,407 | 181,266 | 150,407 |
Distributions declared | (34,499) | (34,512) | (36,669) | (38,265) |  |  |
Net increase (decrease) in net assets resulting from operations | 34,468 | 34,524 | 38,200 | 37,325 |  |  |
Ending of the period | 181,247 | 181,278 | 150,998 | 149,467 | 181,247 | 150,998 | 181,247
Accumulated Net Realized (Losses) Gains |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | (103,454) | (141,279) | (111,845) | (100,015) | (141,279) | (100,015) |
Net increase (decrease) in net assets resulting from operations | 13,389 | 37,825 | (31,166) | (11,830) |  |  |
Ending of the period | (90,065) | (103,454) | (143,011) | (111,845) | (90,065) | (143,011) | (90,065)
Net Unrealized Appreciation (Depreciation) |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | (102,515) | (53,579) | (60,823) | (62,736) | (53,579) | (62,736) |
Net increase (decrease) in net assets resulting from operations | (40,083) | (48,936) | 27,437 | 1,913 |  |  |
Ending of the period | (142,598) | (102,515) | (33,386) | (60,823) | (142,598) | (33,386) | (142,598)
Non-Controlling Interest in NMNLC |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of the period | 5,966 | 5,952 | 12,251 | 11,772 | 5,952 | 11,772 |
Distributions declared | (90) | (90) | (165) | (197) |  |  |
Net increase (decrease) in net assets resulting from operations | 101 | 104 | 313 | 676 | 205 | 989 |
Ending of the period | $ 5,977 | $ 5,966 | $ 12,399 | $ 12,251 | $ 5,977 | $ 12,399 | $ 5,977

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