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Amount of liabilities incurred and payable to vendors for goods and services received, and accrued liabilities classified as other.

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Amount of expense for administrative fee from service provided, including, but not limited to, salary, rent, or overhead cost.

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Amount of fee payable for management of operations based on performance under arrangement, including, but not limited to, investment.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Percentage of total assets less all liabilities and indebtedness not represented by senior security, to senior security representing indebtedness.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Investment Company Act of 1940
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Base rate for management and service fees under arrangement to manage operations, including, but not limited to, investment.

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Rate based on performance for management and service fees under arrangement to manage operations, including, but not limited to, investment.

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Amount of transactions with related party during the financial reporting period.

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AGREEMENTS - Narrative (Details) $ in Millions			3 Months Ended		6 Months Ended		237 Months Ended
AGREEMENTS - Narrative (Details) $ in Millions	Jun. 21, 2019	Jun. 20, 2019	Jun. 30, 2024 USD ($) qtr	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) qtr	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) qtr	Dec. 31, 2023 USD ($)
Investment Company, Financial Highlights [Line Items]
Asset coverage requirement applicable to senior securities	150.00%	200.00%	194.00%		194.00%		194.00%
Number of quarters considered in base management fee calculation \| qtr			2		2		2
Related party transaction amounts payable					$ 0	$ 0
Capital gains incentive fee payable			$ 100		100		$ 100	$ 88
Administrative and other fees			3	$ 3	6	$ 6
Accounts payable and other liabilities			237		$ 237		237	234
Investment Advisory and Management Agreement \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Termination notice period					60 days
Asset coverage requirement applicable to senior securities	150.00%	200.00%
Payments of capital gains incentive fees							133
Investment Advisory and Management Agreement \| Controlled Affiliate \| Minimum
Investment Company, Financial Highlights [Line Items]
Base management fee rate	1.00%	1.50%
Debt to equity leverage ratio	100.00%
Investment Advisory and Management Agreement \| Controlled Affiliate \| Maximum
Investment Company, Financial Highlights [Line Items]
Base management fee rate	1.50%
Debt to equity leverage ratio	100.00%
Incentive Rate, Quarterly Hurdle Rate \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Incentive fee					1.75%
Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Incentive fee					100.00%
Incentive Rate, Quarterly Catch-Up Threshold \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Incentive fee					2.1875%
Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Incentive fee					20.00%
Incentive Rate, Realized Capital Gains \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Incentive fee	20.00%				20.00%
Incentive Rate, Net Assets For Deferral Of Cash Payments \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Incentive fee	7.00%
Capital Gains Incentive Fees \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Related party transaction amounts payable			0	$ 0
Administration Agreement \| Controlled Affiliate
Investment Company, Financial Highlights [Line Items]
Termination notice period	60 days
Accounts payable and other liabilities			$ 7		$ 7		$ 7	$ 4