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Distributions - Costs of Investments for Tax Purposes (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
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Income Tax Disclosure [Abstract] |  |  |
Tax cost | $ 3,209,491 | $ 3,114,145 | $ 2,950,729
Gross unrealized appreciation on investments | 438,214 | 343,520 | 190,217
Gross unrealized depreciation on investments | (409,919) | (298,616) | (181,579)
Total investments at fair value | $ 3,237,786 | $ 3,159,049 | $ 2,959,367

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- Definition The aggregate cost of investments for Federal income tax purposes. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(h)(2)(iv)) -URI https://asc.fasb.org/extlink&oid=126898976&loc=d3e600178-122990 + Details
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- Definition Aggregate gross unrealized appreciation for all Investments in which there is an excess of value over tax cost. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(h)(2)(i)) -URI https://asc.fasb.org/extlink&oid=126898976&loc=d3e600178-122990 + Details
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- Definition The aggregate gross unrealized depreciation for all Investments in which there is an excess of tax cost over value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 946 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.6-03(h)(2)(ii)) -URI https://asc.fasb.org/extlink&oid=126898976&loc=d3e600178-122990 + Details
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