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Distributions - Costs of Investments for Tax Purposes (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Tax cost	$ 2,927,312	$ 3,209,491	$ 3,114,145
Gross unrealized appreciation on investments	466,794	438,214	343,520
Gross unrealized depreciation on investments	(366,284)	(409,919)	(298,616)
Total investments at fair value	$ 3,027,822	$ 3,237,786	$ 3,159,049

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Tax Basis Of Investments, Fair Value For Income Tax Purposes

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Amount of cost of investment for federal income tax purpose.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(h)(2)(iv))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

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Amount of cumulative increase in investment from unrealized gain when value exceeds cost for federal income tax purpose.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(h)(2)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

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Amount of cumulative decrease in investment from unrealized loss when cost for federal income tax purpose exceeds value.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(h)(2)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

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