v3.25.2

Portfolio Investments - Schedule of Roll-Forward in the Changes in Fair Value (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value, beginning balance | $ 2,552,861 | $ 2,667,425 | $ 2,723,732 | $ 2,619,912
Purchases | 140,665 | 224,605 | 567,786 | 713,464
Sales and repayments | (221,661) | (113,234) | (682,652) | (512,974)
Transfers in | 7,617 |  | 17,281 | 63,237
Transfers out | (19,490) |  | (85,119) | (44,643)
Capitalized PIK interest income | 5,070 | 6,901 | 15,359 | 19,256
Accretion of OID | 3,798 | 2,949 | 11,106 | 9,083
Fair value, ending balance | 2,485,322 | 2,752,039 | 2,485,322 | 2,752,039
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | $ 15,018 | $ (51,050) | $ (92,908) | $ (80,128)
Unrealized gain (loss), location | Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax | Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax | Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax | Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax
Net unrealized appreciation (depreciation) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | $ 17,692 | $ 32,498 | $ (64,520) | $ (26,992)
Gain (loss), location | Net unrealized appreciation (depreciation) | Net unrealized appreciation (depreciation) | Net unrealized appreciation (depreciation) | Net unrealized appreciation (depreciation)
Net realized gains (losses) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | $ (1,230) | $ (69,105) | $ (17,651) | $ (88,304)
Gain (loss), location | Realized gain (loss) | Realized gain (loss) | Realized gain (loss) | Realized gain (loss)
Senior secured debt |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value, beginning balance | $ 2,165,740 | $ 2,327,422 | $ 2,320,310 | $ 2,292,691
Purchases | 140,532 | 193,956 | 564,070 | 656,630
Sales and repayments | (219,233) | (113,234) | (679,251) | (506,977)
Transfers in | 0 |  | 6,555 | 23,535
Transfers out | (19,080) |  | (84,709) | (38,544)
Capitalized PIK interest income | 4,357 | 6,287 | 13,258 | 17,571
Accretion of OID | 3,377 | 2,600 | 9,911 | 8,099
Fair value, ending balance | 2,076,845 | 2,393,159 | 2,076,845 | 2,393,159
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | (183) | (36,501) | (84,243) | (54,217)
Investment exchanged, cost | 7,200 |  | 30,900 | 38,500
Senior secured debt | Net unrealized appreciation (depreciation) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | 1,892 | 7,640 | (57,013) | (10,702)
Senior secured debt | Net realized gains (losses) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | (740) | (31,512) | (16,286) | (49,144)
Subordinated debt |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value, beginning balance | 256,925 | 200,115 | 255,346 | 189,724
Purchases | 0 | 30,480 | 3,583 | 47,507
Sales and repayments | (64) | 0 | (229) | (4,932)
Transfers in | 0 |  | 0 | 0
Transfers out | 0 |  | 0 | (4,657)
Capitalized PIK interest income | 713 | 614 | 2,101 | 1,685
Accretion of OID | 421 | 349 | 1,195 | 984
Fair value, ending balance | 257,498 | 230,484 | 257,498 | 230,484
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | (497) | (1,074) | (4,498) | (454)
Subordinated debt | Net unrealized appreciation (depreciation) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | (497) | (1,074) | (4,498) | 127
Subordinated debt | Net realized gains (losses) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | 0 | 0 | 0 | 46
Preferred equity |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value, beginning balance | 70,147 | 62,602 | 66,320 | 86,057
Purchases | 109 | 0 | 109 | 7,578
Sales and repayments | 0 | 0 | (587) | (205)
Transfers in | 410 |  | 1,056 | 0
Transfers out | 0 |  | 0 | (1,159)
Capitalized PIK interest income | 0 | 0 | 0 | 0
Accretion of OID | 0 | 0 | 0 | 0
Fair value, ending balance | 73,232 | 63,892 | 73,232 | 63,892
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | 2,559 | 1,287 | 6,342 | 3,276
Investment exchanged, cost |  |  | 600 | 4,700
Preferred equity | Net unrealized appreciation (depreciation) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | 2,566 | 38,883 | 6,997 | 9,214
Preferred equity | Net realized gains (losses) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | 0 | (37,593) | (663) | (37,593)
Common equity and warrants |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Fair value, beginning balance | 60,049 | 77,286 | 81,756 | 51,440
Purchases | 24 | 169 | 24 | 1,749
Sales and repayments | (2,364) | 0 | (2,585) | (860)
Transfers in | 7,207 |  | 9,670 | 39,702
Transfers out | (410) |  | (410) | (283)
Capitalized PIK interest income | 0 | 0 | 0 | 0
Accretion of OID | 0 | 0 | 0 | 0
Fair value, ending balance | 77,747 | 64,504 | 77,747 | 64,504
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | 13,139 | (14,762) | (10,509) | (28,733)
Investment exchanged, cost | 400 |  | 9,700 | 1,200
Common equity and warrants | Net unrealized appreciation (depreciation) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | 13,731 | (12,951) | (10,006) | (25,631)
Common equity and warrants | Net realized gains (losses) |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Total gains or losses included in earnings | (490) | $ 0 | (702) | (1,613)
Investment, Change in Market Quotes or Liquidity |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Transfers in | $ 11,900 |  | 6,600 | 18,900
Transfers out |  |  | (43,500) |
Common Stock |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Investment exchanged, cost |  |  | $ 400 | $ 300

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