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BORROWINGS - Average stated interest rates and average outstanding balances (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025	Sep. 29, 2025	Aug. 31, 2023	Aug. 24, 2023	Dec. 06, 2021	Nov. 24, 2021	Dec. 04, 2020	Oct. 20, 2020
Debt Instrument [Line Items]
Amortization of debt issuance costs			$ 615	$ 624
JPM Credit Facility
Debt Instrument [Line Items]
Stated Interest Expense	$ 177	$ 2,717	489	6,077
Amortization of debt issuance costs	83	83	166	188
Total interest and other debt financing costs	260	2,800	655	6,265
Capital paid for interest expense	189	$ 3,527	517	$ 7,014
Annualized average stated interest rate		6.40%		6.50%	6.54%
Average outstanding balance		$ 136,630		$ 155,881
2025 CLO Notes
Debt Instrument [Line Items]
Stated Interest Expense	2,356	611	4,767	611
Amortization of debt issuance costs	44	10	89	10
Total interest and other debt financing costs	2,400	$ 621	4,856	$ 621
Capital paid for interest expense	$ 2,336		$ 4,816
Annualized average stated interest rate	5.40%	6.00%	5.40%	6.00%
Average outstanding balance	$ 174,000	$ 40,154	$ 174,000	$ 20,188
Senior Unsecured Notes
Debt Instrument [Line Items]
Stated Interest Expense	1,970	2,507	3,940	5,015
Amortization of debt issuance costs	180	213	360	426
Total interest and other debt financing costs	2,150	2,720	4,300	5,441
Capital paid for interest expense	$ 3,260	$ 4,335	$ 3,940	$ 5,015
Annualized average stated interest rate	5.10%	5.16%	5.10%	5.16%
Average outstanding balance	$ 154,500	$ 194,500	$ 154,500	$ 194,500
5.375% 2025 Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.375%	5.375%	5.375%	5.375%		5.375%						5.375%
5.375% 2026 Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.375%	5.375%	5.375%	5.375%	5.375%						5.375%
4.000% 2026 Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	4.00%	4.00%	4.00%	4.00%	4.00%					4.00%
5.625% 2027 Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	5.625%	5.625%	5.625%	5.625%	5.625%						5.625%
4.250% 2028 Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	4.25%	4.25%	4.25%	4.25%	4.25%				4.25%
7.875% 2028 Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	7.875%	7.875%	7.875%	7.875%	7.875%		7.875%	7.875%