BORROWINGS - Narrative (Details) - USD ($)											9 Months Ended	12 Months Ended
	Mar. 20, 2025	Oct. 04, 2024	Oct. 03, 2024	Jun. 14, 2024	Mar. 14, 2024	Dec. 07, 2023	Nov. 21, 2023	Nov. 20, 2023	Jun. 23, 2023	May 20, 2022	Sep. 30, 2025	Dec. 31, 2024	Jan. 22, 2025	Sep. 30, 2024	Dec. 06, 2023
Debt Instrument [Line Items]
Asset coverage ratio (as a percent)											179.82%	187.03%		189.89%
Amount available											$ 269,500,000	$ 206,250,000
Total Commitment											1,373,814,000	1,321,179,000
CLO-I | Secured Debt
Debt Instrument [Line Items]
Amount available											0	0
Total Commitment											321,242,000	342,000,000
Debt securitization										$ 448,325,000
AAA Class A-1 2022 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization										$ 199,000,000
AAA Class A-1 2022 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)										1.80%
AAA Class A-1F 2022 Notes | Secured Debt
Debt Instrument [Line Items]
Interest rate (as a percent)										4.42%
Debt securitization										$ 34,250,000
AA Class B 2022 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization										$ 47,250,000
AA Class B 2022 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)										2.30%
A Class C 2022 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization										$ 31,500,000
A Class C 2022 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)										3.15%
BBB Class D 2022 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization										$ 27,000,000
BBB Class D 2022 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)										4.15%
Subordinated 2022 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization										$ 79,325,000
AAA Class A-L 2022 Loans to CLO-I | Secured Debt
Debt Instrument [Line Items]
Debt securitization										$ 30,000,000
AAA Class A-L 2022 Loans to CLO-I | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)										1.80%
CLO-I Refinancing | Secured Debt
Debt Instrument [Line Items]
Debt securitization	$ 457,975,000									$ 79,325,000
AA Class X 2025 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization	$ 1,900,000
AA Class X 2025 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)	1.05%
AAA Class A-R 2025 Notes | Secured Debt
Debt Instrument [Line Items]
Interest rate (as a percent)	1.38%
Debt securitization	$ 233,250,000
AA Class B-R 2025 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization	$ 56,250,000
AA Class B-R 2025 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)	1.70%
Subordinated 2025 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization	$ 136,575,000
AAA Class A-L-R 2025 Loans to CLO-I | Secured Debt
Debt Instrument [Line Items]
Debt securitization	$ 30,000,000
Class A-L-R 2025 Loans | Secured Debt
Debt Instrument [Line Items]
Interest rate (as a percent)	1.38%
2023 Debt | Secured Debt
Debt Instrument [Line Items]
Amount available											0	0
Total Commitment											213,572,000	214,429,000
Debt securitization						$ 298,060,000
AAA Class X 2023 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization						$ 2,000,000
AAA Class X 2023 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)						2.00%
AAA Class A-1 2023 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization						$ 100,500,000
AAA Class A-1 2023 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)						2.35%
AA Class B 2023 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization						$ 37,500,000
AA Class B 2023 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)						3.20%
Subordinated 2023 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization						$ 83,060,000
AAA Class A-L-A 2023 to CLO-II | Secured Debt
Debt Instrument [Line Items]
Debt securitization						$ 25,000,000
AAA Class A-L-A 2023 to CLO-II | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)						2.35%
AAA Class A-L-B 2023 Loans to CLO-II | Secured Debt
Debt Instrument [Line Items]
Debt securitization						$ 50,000,000
AAA Class A-L-B 2023 Loans to CLO-II | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)						2.35%
2024 Debt | Secured Debt
Debt Instrument [Line Items]
Amount available											0	0
Total Commitment											214,000,000	214,750,000
Debt securitization					$ 296,970,000
AAA Class X 2024 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization					$ 2,000,000
AAA Class X 2024 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)					1.40%
AAA Class A 2024 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization					$ 175,500,000
AAA Class A 2024 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)					2.00%
AA Class B 2024 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization					$ 37,500,000
AA Class B 2024 Notes | Secured Debt | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)					2.65%
Subordinated 2024 Notes | Secured Debt
Debt Instrument [Line Items]
Debt securitization					$ 81,970,000
2030 Notes
Debt Instrument [Line Items]
Total Commitment													$ 300,000,000
Stated interest rate (as a percent)													6.65%
Secured Debt | Wells Fargo Financing Facility | Credit Facility
Debt Instrument [Line Items]
Amount available												119,000,000
Line of credit facility, unused capacity, commitment fee percentage, less than forty percent of total commitments (as a percent)				0.50%
Line of credit facility, maximum borrowing capacity (as a percent)				40.00%
Line of credit facility, unused capacity, commitment fee percentage, in excess of forty percent of total commitments (as a percent)				1.50%
Total Commitment												225,000,000
Secured Debt | Wells Fargo Financing Facility - Daily Undrawn Amounts During the Period | Credit Facility
Debt Instrument [Line Items]
Amount available											225,000,000
Unused commitment fee (as a percent)				0.25%
Secured Debt | Wells Fargo Financing Facility - for Next Six Months and Thereafter | Credit Facility
Debt Instrument [Line Items]
Unused commitment fee (as a percent)				0.50%
Secured Debt | SMBC Financing Facility | Credit Facility
Debt Instrument [Line Items]
Unused commitment fee (as a percent)								0.50%
Total Commitment						$ 150,000,000									$ 300,000,000
Subsequent increase						$ 250,000,000
Unused commitment fee percentage, less than fifty percent of total commitments (as a percent)							0.50%
Unused commitment fee percentage, more than fifty percent of total commitments (as a percent)							1.00%
Secured Debt | SMBC Financing Facility | Credit Facility | Base Rate
Debt Instrument [Line Items]
Interest rate (as a percent)							1.65%
Secured Debt | SMBC Financing Facility | Credit Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)							2.65%
Secured Debt | Revolving Credit Facility | Credit Facility
Debt Instrument [Line Items]
Amount available											269,500,000	87,250,000
Unused commitment fee (as a percent)									0.375%
Total Commitment		$ 325,000,000	$ 250,000,000								$ 325,000,000	$ 325,000,000
Interest rate (as a percent)		2.00%	2.125%
Secured Debt | Revolving Credit Facility | Credit Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Interest rate (as a percent)											2.00%	2.00%
Secured Debt | Revolving Credit Facility | Credit Facility | Three Month SOFR
Debt Instrument [Line Items]
Credit spread adjustment (as a percent)		0.10%	0.15%
Secured Debt | Revolving Credit Facility | Credit Facility | Six Month SOFR
Debt Instrument [Line Items]
Credit spread adjustment (as a percent)		0.10%	0.25%
Secured Debt | Revolving Credit Facility | Credit Facility | All Other Borrowing Rates
Debt Instrument [Line Items]
Credit spread adjustment (as a percent)		1.00%	1.125%
Secured Debt | 2030 Notes | Credit Facility
Debt Instrument [Line Items]
Amount available											$ 0
Total Commitment											$ 300,000,000
Bridge Loan | Revolving Credit Facility | Credit Facility
Debt Instrument [Line Items]
Total Commitment									$ 25,000,000