COMMITMENTS AND CONTINGENCIES - Loan Commitments (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Other Commitments [Line Items]
Total net adjusted unfunded loan commitments	$ 25.0	$ 29.0
Revolving and delayed draw loan commitments
Other Commitments [Line Items]
Total revolving loan commitments	4,788.4	4,447.5
Less: funded commitments	(539.0)	(529.3)
Less: unavailable delayed draw loan commitments due to borrowing base or other covenant restrictions	(26.5)	(23.1)
Total net adjusted unfunded loan commitments	4,249.4	3,918.2
Total net unfunded revolving and delayed draw loan commitments	4,222.9	3,895.1
Revolving loan commitments
Other Commitments [Line Items]
Total revolving loan commitments	2,469.0	2,254.0
Less: funded commitments	(539.0)	(529.0)
Less: unavailable delayed draw loan commitments due to borrowing base or other covenant restrictions	(12.0)	(1.0)
Total net adjusted unfunded loan commitments	1,918.0	1,724.0
Delayed draw loan commitments
Other Commitments [Line Items]
Total revolving loan commitments	2,320.0	2,193.0
Less: unavailable delayed draw loan commitments due to borrowing base or other covenant restrictions	(15.0)	(22.0)
Total net adjusted unfunded loan commitments	$ 2,305.0	$ 2,171.0

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 16
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-16

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Amount of financial support committed by investment company to investee that is contractually required.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-15

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480990/946-20-50-15

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