v3.26.3
FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of Significant Unobservable Inputs used to Value Investments (Details)
Sep. 30, 2026
USD ($)
Dec. 31, 2025
USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 21,355,776,100 [1] $ 21,508,598,400 [2]
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value 17,012,206,000 14,497,808,000
Level 3 | First lien senior secured loans | Yield analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 12,014,290,000 $ 10,364,836,000
Level 3 | First lien senior secured loans | Yield analysis | Market yield | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.060 0.055
Level 3 | First lien senior secured loans | Yield analysis | Market yield | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.195 0.191
Level 3 | First lien senior secured loans | Yield analysis | Market yield | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.097 0.091
Level 3 | First lien senior secured loans | Broker quotes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 215,464,000 $ 167,884,000
Level 3 | First lien senior secured loans | Transaction cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value   10,150,000
Level 3 | Second lien senior secured loans | Yield analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 158,538,000 $ 141,949,000
Level 3 | Second lien senior secured loans | Yield analysis | Market yield | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.091 0.082
Level 3 | Second lien senior secured loans | Yield analysis | Market yield | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.293 0.196
Level 3 | Second lien senior secured loans | Yield analysis | Market yield | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.183 0.129
Level 3 | Senior subordinated loans | Yield analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 1,313,879,000 $ 1,032,512,000
Level 3 | Senior subordinated loans | Yield analysis | Market yield | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.076 0.070
Level 3 | Senior subordinated loans | Yield analysis | Market yield | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.161 0.247
Level 3 | Senior subordinated loans | Yield analysis | Market yield | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.106 0.106
Level 3 | Senior subordinated loans | Transaction cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value   $ 31,244,000
Level 3 | Corporate bonds | Broker quotes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 62,294,000 99,063,000
Level 3 | Collateralized loan obligations | Broker quotes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value 714,587,000 1,047,274,000
Level 3 | Collateralized loan obligations | Transaction cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value   3,990,000
Level 3 | Commercial mortgage-backed securities | Broker quotes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value 59,937,000 99,962,000
Level 3 | Commercial mortgage-backed securities | Discounted cash flow    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 49,705,000  
Level 3 | Commercial mortgage-backed securities | Discounted cash flow | Discount rate | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.072  
Level 3 | Commercial mortgage-backed securities | Discounted cash flow | Discount rate | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.152  
Level 3 | Commercial mortgage-backed securities | Discounted cash flow | Discount rate | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.128  
Level 3 | Private asset-backed investments | Yield analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 299,037,000 $ 202,865,000
Level 3 | Private asset-backed investments | Yield analysis | Market yield | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.070 0.040
Level 3 | Private asset-backed investments | Yield analysis | Market yield | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.150 0.138
Level 3 | Private asset-backed investments | Yield analysis | Market yield | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.111 0.087
Level 3 | Private asset-backed investments | Broker quotes    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value   $ 50,750,000
Level 3 | Private asset-backed investments | Transaction cost    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value   41,570,000
Level 3 | Private asset-backed investments | Discounted cash flow    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 21,337,000  
Level 3 | Private asset-backed investments | Discounted cash flow | Constant default rate | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.048  
Level 3 | Private asset-backed investments | Discounted cash flow | Constant default rate | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.167  
Level 3 | Private asset-backed investments | Discounted cash flow | Constant default rate | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.140  
Level 3 | Private asset-backed investments | Income (other)    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 7,527,000 $ 5,762,000
Level 3 | Private asset-backed investments | Income (other) | Constant default rate | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.020 0.000
Level 3 | Private asset-backed investments | Income (other) | Constant default rate | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.070 0.070
Level 3 | Private asset-backed investments | Income (other) | Constant default rate | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.034 0.017
Level 3 | Investments in joint ventures | Yield analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value   $ 391,000,000
Level 3 | Investments in joint ventures | Yield analysis | Market yield    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input   0.100
Level 3 | Investments in joint ventures | Yield analysis | Market yield | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input   0.100
Level 3 | Investments in joint ventures | Net asset value analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 1,003,200,000  
Level 3 | Preferred equity | Yield analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 379,998,000 $ 152,001,000
Level 3 | Preferred equity | Yield analysis | Market yield | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.080 0.098
Level 3 | Preferred equity | Yield analysis | Market yield | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.150 0.150
Level 3 | Preferred equity | Yield analysis | Market yield | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.126 0.129
Level 3 | Preferred equity | EV market multiple analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 76,887,000 $ 165,475,000
Level 3 | Preferred equity | EV market multiple analysis | EBITDA multiple | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.058 0.071
Level 3 | Preferred equity | EV market multiple analysis | EBITDA multiple | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.24 0.225
Level 3 | Preferred equity | EV market multiple analysis | EBITDA multiple | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 0.101 0.124
Level 3 | Other equity | EV market multiple analysis    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Fair Value $ 635,526,000 $ 489,521,000
Level 3 | Other equity | EV market multiple analysis | EBITDA multiple | Minimum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 3.8 0.072
Level 3 | Other equity | EV market multiple analysis | EBITDA multiple | Maximum    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 30.1 0.33
Level 3 | Other equity | EV market multiple analysis | EBITDA multiple | Weighted Average    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Unobservable Input 15 15.1
[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.