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Distributions - Reconciliation Between GAAP-Basis Net Investment Income And Tax-basis Net Investment Income (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2025	Sep. 30, 2025	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Investment Company [Abstract]
GAAP-basis net investment income	$ 135	$ 159	$ 173	$ 187	$ 171	$ 215	$ 215	$ 212	$ 654	$ 813	$ 892
Income subject to tax not recorded for GAAP									86	(35)	74
GAAP accretion from merger not recognized for tax									(24)	(33)	(46)
Excise taxes									22	23	22
GAAP versus tax-basis impact of consolidation of certain subsidiaries									1	6	6
Reclassification of unamortized original issue discount and prepayment fees									(13)	(21)	(3)
Other miscellaneous differences									(74)	(18)	(2)
Tax-basis net investment income									$ 652	$ 735	$ 943

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Amount, after expense and tax, of investment income classified as operating. Excludes realized and unrealized gain (loss) on investment.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 946
-SubTopic 830
-Name Accounting Standards Codification
-Section 55
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479168/946-830-55-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147478009/946-205-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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-Publisher FASB
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