v3.23.3

Portfolio Investments - Roll-Forward in the Changes in Fair Value (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | $ 2,169,475 | $ 2,161,581
Purchases (a) | 1,131,251 | 520,510
Sales and repayments | (665,727) | (512,535)
Transfers in | 59,168 | 49,843
Transfers out | (40,093) | (22,908)
Capitalized PIK interest income | 15,644 | 23,168
Accretion of OID | 17,771 | 26,482
Fair value, ending balance | $ 2,619,912 | $ 2,169,475
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | 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) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | $ (63,990) | $ (72,913)
Net unrealized appreciation (depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Net unrealized appreciation (depreciation) | Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax
Total gains or losses included in earnings | $ (48,971) | $ (81,863)
Net realized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Realized gain (loss) | Gain (Loss), Investment and Derivative, Operating, and Foreign Currency Transaction, after Tax
Total gains or losses included in earnings | $ (18,606) | $ 5,197
Senior secured debt |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 1,910,606 | 1,878,536
Purchases (a) | 1,080,654 | 490,081
Sales and repayments | (650,437) | (476,813)
Transfers in | 19,075 | 49,843
Transfers out | (40,093) | (17,070)
Capitalized PIK interest income | 15,016 | 22,855
Accretion of OID | 16,322 | 24,422
Fair value, ending balance | 2,292,691 | 1,910,606
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | (48,680) | (53,013)
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 | (37,253) | (67,455)
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 | (21,199) | 6,207
Subordinated debt |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 159,388 | 176,317
Purchases (a) | 30,690 | 7,960
Sales and repayments | (1,396) | (22,525)
Transfers in | 0 | 0
Transfers out | 0 | 0
Capitalized PIK interest income | 628 | 313
Accretion of OID | 1,449 | 2,060
Fair value, ending balance | 189,724 | 159,388
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | (1,035) | (4,885)
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 | (1,035) | (4,737)
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
Preferred equity |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 79,523 | 63,565
Purchases (a) | 14,296 | 19,662
Sales and repayments | 0 | (163)
Transfers in | 0 | 0
Transfers out | 0 | 0
Capitalized PIK interest income | 0 | 0
Accretion of OID | 0 | 0
Fair value, ending balance | 86,057 | 79,523
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | (7,762) | (3,264)
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 | (7,762) | (3,029)
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 | (512)
Common equity and warrants |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 19,958 | 43,163
Purchases (a) | 5,611 | 2,807
Sales and repayments | (13,894) | (13,034)
Transfers in | 40,093 | 0
Transfers out | 0 | (5,838)
Capitalized PIK interest income | 0 | 0
Accretion of OID | 0 | 0
Fair value, ending balance | 51,440 | 19,958
Net unrealized appreciation (depreciation) relating to Level 3 investments still held and reported within net unrealized appreciation (depreciation) in the Consolidated Statement of Operations | (6,513) | (11,751)
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 | (2,921) | (6,642)
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 | $ 2,593 | $ (498)

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- Definition Indicates line item in statement in which net income is reported that includes unrealized gain (loss) from asset measured at fair value using unobservable input (level 3) and still held. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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