v3.26.3
INVESTMENTS - Schedule of Investments (Details)
 9 Months Ended 12 Months Ended
Sep. 30, 2026
USD ($)
Dec. 31, 2025
USD ($)
Schedule of Investments [Line Items]    
Amortized Cost $ 21,511,938,300 [1] $ 21,360,914,400 [2]
Fair Value 21,355,776,100 [1] 21,508,598,400 [2]
Software and Services    
Schedule of Investments [Line Items]    
Amortized Cost 4,709,456,400 4,696,255,400
Fair Value 4,590,005,400 4,725,434,100
Commercial and Professional Services    
Schedule of Investments [Line Items]    
Amortized Cost 2,170,918,000 1,865,620,500
Fair Value 2,156,887,800 1,849,522,600
Investment Funds and Vehicles    
Schedule of Investments [Line Items]    
Amortized Cost 2,158,561,600 1,841,282,500
Fair Value 2,040,006,200 1,826,970,400
Health Care Equipment and Services    
Schedule of Investments [Line Items]    
Amortized Cost 1,993,795,100 2,368,817,900
Fair Value 1,930,104,900 2,368,334,500
Capital Goods    
Schedule of Investments [Line Items]    
Amortized Cost 1,709,229,400 1,663,903,600
Fair Value 1,708,750,500 1,661,724,000
Financial Services    
Schedule of Investments [Line Items]    
Amortized Cost 1,229,802,000  
Fair Value 1,241,847,100  
Insurance    
Schedule of Investments [Line Items]    
Amortized Cost 1,033,093,100  
Fair Value 1,023,802,500  
Consumer Distribution and Retail    
Schedule of Investments [Line Items]    
Amortized Cost 846,028,900 631,418,900
Fair Value 844,062,000 634,669,100
Sports, Media and Entertainment    
Schedule of Investments [Line Items]    
Amortized Cost 698,888,700 776,717,900
Fair Value 801,284,200 817,462,800
Pharmaceuticals, Biotechnology and Life Sciences    
Schedule of Investments [Line Items]    
Amortized Cost 645,827,300 656,406,200
Fair Value 651,344,800 665,524,700
Materials    
Schedule of Investments [Line Items]    
Amortized Cost 396,852,400 370,039,800
Fair Value 382,912,700 355,083,900
Food and Beverage    
Schedule of Investments [Line Items]    
Amortized Cost 322,480,100 324,520,300
Fair Value 330,155,100 $ 330,381,500
Data Centers    
Schedule of Investments [Line Items]    
Amortized Cost 297,899,500  
Fair Value $ 300,997,700  
Investments, At Fair Value | Industry Concentration Risk    
Schedule of Investments [Line Items]    
Composition, percent of fair value 100.00% 100.00%
Investments, At Fair Value | Industry Concentration Risk | Software and Services    
Schedule of Investments [Line Items]    
Composition, percent of fair value 21.50% 22.00%
Investments, At Fair Value | Industry Concentration Risk | Commercial and Professional Services    
Schedule of Investments [Line Items]    
Composition, percent of fair value 10.10% 8.60%
Investments, At Fair Value | Industry Concentration Risk | Investment Funds and Vehicles    
Schedule of Investments [Line Items]    
Composition, percent of fair value 9.60% 8.50%
Investments, At Fair Value | Industry Concentration Risk | Health Care Equipment and Services    
Schedule of Investments [Line Items]    
Composition, percent of fair value 9.00% 11.00%
Investments, At Fair Value | Industry Concentration Risk | Capital Goods    
Schedule of Investments [Line Items]    
Composition, percent of fair value 8.00% 7.70%
Investments, At Fair Value | Industry Concentration Risk | Consumer Services    
Schedule of Investments [Line Items]    
Composition, percent of fair value 6.60% 6.00%
Investments, At Fair Value | Industry Concentration Risk | Financial Services    
Schedule of Investments [Line Items]    
Composition, percent of fair value 5.80% 6.70%
Investments, At Fair Value | Industry Concentration Risk | Insurance    
Schedule of Investments [Line Items]    
Composition, percent of fair value 4.80% 5.10%
Investments, At Fair Value | Industry Concentration Risk | Consumer Distribution and Retail    
Schedule of Investments [Line Items]    
Composition, percent of fair value 4.00% 3.00%
Investments, At Fair Value | Industry Concentration Risk | Sports, Media and Entertainment    
Schedule of Investments [Line Items]    
Composition, percent of fair value 3.80% 3.80%
Investments, At Fair Value | Industry Concentration Risk | Pharmaceuticals, Biotechnology and Life Sciences    
Schedule of Investments [Line Items]    
Composition, percent of fair value 3.00% 3.10%
Investments, At Fair Value | Industry Concentration Risk | Materials    
Schedule of Investments [Line Items]    
Composition, percent of fair value 1.80% 1.70%
Investments, At Fair Value | Industry Concentration Risk | Energy    
Schedule of Investments [Line Items]    
Composition, percent of fair value 1.70% 1.90%
Investments, At Fair Value | Industry Concentration Risk | Food and Beverage    
Schedule of Investments [Line Items]    
Composition, percent of fair value 1.50% 1.50%
Investments, At Fair Value | Industry Concentration Risk | Data Centers    
Schedule of Investments [Line Items]    
Composition, percent of fair value 1.40% 0.20%
Investments, At Fair Value | Industry Concentration Risk | Other    
Schedule of Investments [Line Items]    
Composition, percent of fair value 7.40% 9.20%
Investments, At Fair Value | Geographic Concentration Risk    
Schedule of Investments [Line Items]    
Composition, percent of fair value 100.00% 100.00%
Investments, At Fair Value | Geographic Concentration Risk | United States    
Schedule of Investments [Line Items]    
Composition, percent of fair value 89.70% 86.70%
Investments, At Fair Value | Geographic Concentration Risk | Europe    
Schedule of Investments [Line Items]    
Composition, percent of fair value 5.80% 7.50%
Investments, At Fair Value | Geographic Concentration Risk | Bermuda/Cayman Islands    
Schedule of Investments [Line Items]    
Composition, percent of fair value 3.10% 4.50%
Investments, At Fair Value | Geographic Concentration Risk | Canada    
Schedule of Investments [Line Items]    
Composition, percent of fair value 1.10% 1.30%
Investments, At Fair Value | Geographic Concentration Risk | Other    
Schedule of Investments [Line Items]    
Composition, percent of fair value 0.30% 0.00%
First lien senior secured loans    
Schedule of Investments [Line Items]    
Amortized Cost $ 16,471,161,000 $ 17,143,966,000
Fair Value 16,263,640,000 17,160,266,000
Second lien senior secured loans    
Schedule of Investments [Line Items]    
Amortized Cost 392,220,000 430,463,000
Fair Value 349,181,000 429,160,000
Senior subordinated loans    
Schedule of Investments [Line Items]    
Amortized Cost 1,300,777,000 1,003,023,000
Fair Value 1,315,808,000 1,068,842,000
Corporate bonds    
Schedule of Investments [Line Items]    
Amortized Cost 62,600,000 97,600,000
Fair Value 62,294,000 99,063,000
Collateralized loan obligations    
Schedule of Investments [Line Items]    
Amortized Cost 843,304,000 1,081,583,000
Fair Value 714,587,000 1,051,264,000
Commercial mortgage-backed securities    
Schedule of Investments [Line Items]    
Amortized Cost 110,102,000 98,850,000
Fair Value 109,642,000 99,962,000
Private asset-backed investments    
Schedule of Investments [Line Items]    
Amortized Cost 311,937,000 289,022,000
Fair Value 327,901,000 300,947,000
Investments in joint ventures    
Schedule of Investments [Line Items]    
Amortized Cost 1,003,200,000 391,000,000
Fair Value 1,003,200,000 391,000,000
Preferred equity    
Schedule of Investments [Line Items]    
Amortized Cost 441,409,000 302,430,000
Fair Value 466,777,000 317,476,000
Other equity    
Schedule of Investments [Line Items]    
Amortized Cost 575,228,000 522,977,000
Fair Value 742,746,000 590,618,000
Subordinated Certificates of ADLP    
Schedule of Investments [Line Items]    
Amortized Cost 1,003,200,000 391,000,000
Fair Value $ 1,003,200,000 $ 391,000,000
Amortized Cost 0.135 0.130
Fair Value 0.135 0.130
[1] As of September 30, 2026, the estimated net unrealized loss for federal tax purposes was approximately $128.4 million based on a tax cost basis of approximately $21.5 billion. As of September 30, 2026, the estimated aggregate gross unrealized loss for federal income tax purposes was approximately $518.0 million and the estimated aggregate gross unrealized gain for federal income tax purposes was $389.6 million.
[2] As of December 31, 2025, the estimated net unrealized gain for federal tax purposes was approximately $206.8 million based on a tax cost basis of approximately $21.3 billion. As of December 31, 2025, the estimated aggregate gross unrealized gain for federal income tax purposes was $354.9 million and the estimated aggregate gross unrealized loss for federal income tax purposes was $148.1 million.