Significant Agreements And Related Party Transactions - Schedule of Affiliated Investments (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	$ 3,506,216
Ending Fair Value Balance	3,514,903	$ 3,506,216
Investment, Identifier [Axis]: Controlled Affiliates
Schedule Of Investments [Line Items]
Beginning Fair Value Balance		18,375
Gross Additions		22,066
Gross Reductions		(18,660)
Net Realized Gain(Loss)		(14,414)
Net Change in Unrealized Appreciation (Depreciation)		(7,367)
Dividend, Interest, PIK and Other Income		275
Investment, Identifier [Axis]: Controlled Affiliates Bolttech Mannings, Inc
Schedule Of Investments [Line Items]
Beginning Fair Value Balance		18,375
Gross Additions		22,066
Gross Reductions		(18,660)
Net Realized Gain(Loss)		(14,414)
Net Change in Unrealized Appreciation (Depreciation)		(7,367)
Dividend, Interest, PIK and Other Income		275
Investment, Identifier [Axis]: Non-Controlled Affiliates
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	40,991	32,819
Gross Additions	87,772	341,113
Gross Reductions	(87,735)	(329,622)
Net Change in Unrealized Appreciation (Depreciation)	(295)	(3,319)
Ending Fair Value Balance	40,733	40,991
Dividend, Interest, PIK and Other Income	675	2,188
Investment, Identifier [Axis]: Non-Controlled Affiliates ATX Networks Corporation
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	9,059	6,039
Gross Additions	105	195
Gross Reductions	(55)	(633)
Net Change in Unrealized Appreciation (Depreciation)	(275)	3,458
Ending Fair Value Balance	8,834	9,059
Dividend, Interest, PIK and Other Income	175	623
Investment, Identifier [Axis]: Non-Controlled Affiliates Animal Supply Holdings Limited Liability Company
Schedule Of Investments [Line Items]
Beginning Fair Value Balance		6,569
Gross Additions		382
Net Change in Unrealized Appreciation (Depreciation)		(6,951)
Dividend, Interest, PIK and Other Income		380
Investment, Identifier [Axis]: Non-Controlled Affiliates Collaborative Imaging LLC
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	4,926	5,491
Net Change in Unrealized Appreciation (Depreciation)	(684)	(565)
Ending Fair Value Balance	4,242	4,926
Dividend, Interest, PIK and Other Income	54	289
Investment, Identifier [Axis]: Non-Controlled Affiliates Conergy Asia & ME Private Limited
Schedule Of Investments [Line Items]
Beginning Fair Value Balance		400
Net Change in Unrealized Appreciation (Depreciation)		(400)
Investment, Identifier [Axis]: Non-Controlled Affiliates Elah Holdings Inc.
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	5,396	5,396
Ending Fair Value Balance	5,396	5,396
Investment, Identifier [Axis]: Non-Controlled Affiliates Goldman Sachs Financial Square Government Fund
Schedule Of Investments [Line Items]
Gross Additions	87,653	328,935
Gross Reductions	(87,653)	(328,935)
Dividend, Interest, PIK and Other Income	53	93
Investment, Identifier [Axis]: Non-Controlled Affiliates Iracore International Holdings, Inc.
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	8,635	7,596
Net Change in Unrealized Appreciation (Depreciation)	628	1,039
Ending Fair Value Balance	9,263	8,635
Dividend, Interest, PIK and Other Income	81	265
Investment, Identifier [Axis]: Non-Controlled Affiliates Kawa Solar Holdings Limited
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	1,283	1,328
Net Change in Unrealized Appreciation (Depreciation)		(45)
Ending Fair Value Balance	1,283	1,283
Investment, Identifier [Axis]: Non-Controlled Affiliates Southeast Mechanical LLC Dba SEM Holdings LLC
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	11,692
Gross Additions	14	11,601
Gross Reductions	(27)	(54)
Net Change in Unrealized Appreciation (Depreciation)	36	145
Ending Fair Value Balance	11,715	11,692
Dividend, Interest, PIK and Other Income	312	538
Investment, Identifier [Axis]: Total Affiliates
Schedule Of Investments [Line Items]
Beginning Fair Value Balance	40,991	51,194
Gross Additions	87,772	363,179
Gross Reductions	(87,735)	(348,282)
Net Realized Gain(Loss)		(14,414)
Net Change in Unrealized Appreciation (Depreciation)	(295)	(10,686)
Ending Fair Value Balance	40,733	40,991
Dividend, Interest, PIK and Other Income	$ 675	$ 2,463

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Amount of operating dividend income on securities.

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Gross additions to the investment in and advance to the affiliate.

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Gross reductions to the investment in and advance to the affiliate.

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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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