INVESTMENTS - Ivy Hill Asset Management, L.P. (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) borrower	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Schedule of Investments [Line Items]
Amortized cost of investments	$ 22,043.0	$ 19,810.0
Purchases of investments	9,852.0	13,644.0	$ 6,759.0
Ivy Hill Asset Management, L.P.
Schedule of Investments [Line Items]
Amortized cost of investments	2,048.0	781.0
Purchases of investments	27.0
Realized loss on sale of investments	20.0	7.0	21.0
Ivy Hill Asset Management, L.P.
Schedule of Investments [Line Items]
Assets under management	$ 13,100.0
Number of borrowers \| borrower	21
Amortized cost of investments	$ 2,370.0	966.0
Management and incentive fee income	48.0	31.0	28.0
Other investment-related income	189.0	91.0	75.0
Purchases of investments	$ 3,358.0	$ 2,407.0	$ 940.0

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