FAIR VALUE OF FINANCIAL INSTRUMENTS - Significant Unobservable Inputs (Details) $ in Millions	Dec. 31, 2025 USD ($)		Dec. 31, 2024 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	$ 29,484.8	[1]	$ 26,719.9	[2]
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	28,692.0		26,091.0
Level 3 | Yield analysis | First lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	17,584.0		14,722.0
Level 3 | Yield analysis | Second lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	1,063.0		1,724.0
Level 3 | Yield analysis | Senior subordinated loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	1,537.0		1,343.0
Level 3 | Yield analysis | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	2,475.0		2,649.0
Level 3 | Discounted cash flow analysis | Subordinated certificates of the SDLP
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	1,117.0		1,192.0
Level 3 | Discounted cash flow analysis | Ivy Hill Asset Management, L.P.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	2,434.0		1,915.0
Level 3 | EV market multiple analysis | Other equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value	$ 2,482.0		$ 2,546.0
Level 3 | Market yield | Yield analysis | Minimum | First lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.055		0.038
Level 3 | Market yield | Yield analysis | Minimum | Second lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.082		0.096
Level 3 | Market yield | Yield analysis | Minimum | Senior subordinated loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.070		0.084
Level 3 | Market yield | Yield analysis | Minimum | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.070		0.070
Level 3 | Market yield | Yield analysis | Maximum | First lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.236		0.229
Level 3 | Market yield | Yield analysis | Maximum | Second lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.253		0.232
Level 3 | Market yield | Yield analysis | Maximum | Senior subordinated loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.247		0.219
Level 3 | Market yield | Yield analysis | Maximum | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.231		0.190
Level 3 | Market yield | Yield analysis | Weighted Average | First lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.095		0.104
Level 3 | Market yield | Yield analysis | Weighted Average | Second lien senior secured loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.137		0.142
Level 3 | Market yield | Yield analysis | Weighted Average | Senior subordinated loans
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.128		0.128
Level 3 | Market yield | Yield analysis | Weighted Average | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.134		0.133
Level 3 | Discount rate | Discounted cash flow analysis | Minimum | Subordinated certificates of the SDLP
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.094		0.100
Level 3 | Discount rate | Discounted cash flow analysis | Minimum | Ivy Hill Asset Management, L.P.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.093		0.099
Level 3 | Discount rate | Discounted cash flow analysis | Maximum | Subordinated certificates of the SDLP
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.127		0.130
Level 3 | Discount rate | Discounted cash flow analysis | Maximum | Ivy Hill Asset Management, L.P.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.165		0.190
Level 3 | Discount rate | Discounted cash flow analysis | Weighted Average | Subordinated certificates of the SDLP
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.113		0.120
Level 3 | Discount rate | Discounted cash flow analysis | Weighted Average | Ivy Hill Asset Management, L.P.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	0.101		0.114
Level 3 | EBITDA multiple | EV market multiple analysis | Minimum | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	3.5		2.6
Level 3 | EBITDA multiple | EV market multiple analysis | Minimum | Other equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	4.5		5.6
Level 3 | EBITDA multiple | EV market multiple analysis | Maximum | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	26		25.1
Level 3 | EBITDA multiple | EV market multiple analysis | Maximum | Other equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	33		49.7
Level 3 | EBITDA multiple | EV market multiple analysis | Weighted Average | Preferred equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	13.8		15.4
Level 3 | EBITDA multiple | EV market multiple analysis | Weighted Average | Other equity
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Unobservable Input	14.2		18.1

[1] As of December 31, 2025, the estimated net unrealized gain for federal tax purposes was approximately $300 million based on a tax cost basis of $29.2 billion. As of December 31, 2025, the estimated aggregate gross unrealized gain for federal income tax purposes was approximately $1.3 billion and the estimated aggregate gross unrealized loss for federal income tax purposes was approximately $1.0 billion.

[2] As of December 31, 2024, the estimated net unrealized gain for federal tax purposes was $0.2 billion based on a tax cost basis of $26.5 billion. As of December 31, 2024, the estimated aggregate gross unrealized gain for federal income tax purposes was $1.7 billion and the estimated aggregate gross unrealized loss for federal income tax purposes was $1.5 billion.