INVESTMENTS - Amortized Cost and Fair Value of the Investment in IHAM (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Schedule of Investments [Line Items]
Amortized Cost	$ 29,647.5	$ 29,249.9	[1]
Fair Value	29,499.3	29,484.8	[1]
Ivy Hill Asset Management, L.P.
Schedule of Investments [Line Items]
Amortized Cost	2,462.0	2,231.0
Fair Value	2,661.0	2,434.0
Subordinated loan
Schedule of Investments [Line Items]
Amortized Cost	762.0	531.0
Fair Value	762.0	531.0
Commitment to fund	1,000.0	750.0
Equity
Schedule of Investments [Line Items]
Amortized Cost	1,700.0	1,700.0
Fair Value	$ 1,899.0	$ 1,903.0

[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.