XML 42 R32.htm IDEA: XBRL DOCUMENT v3.22.2.2
INVESTMENTS - Additional Information (Details)
$ in Thousands
 3 Months Ended 9 Months Ended 12 Months Ended
Feb. 25, 2022
member
Sep. 30, 2022
USD ($)
investment
loan
Sep. 30, 2021
USD ($)
investment
Sep. 30, 2022
USD ($)
investment
loan
Sep. 30, 2021
USD ($)
investment
Dec. 31, 2021
USD ($)
investment
loan
Jun. 02, 2022
USD ($)
Jul. 08, 2021
USD ($)
Feb. 08, 2021
USD ($)
Dec. 31, 2020
USD ($)
May 08, 2019
USD ($)
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments   $ 183,400 $ 122,100 $ 681,200 $ 529,900            
Total unused commitments to extend financing   299,238   299,238   $ 234,658          
Fair value of investment owned   2,332,492 [1]   2,332,492 [1]   1,800,594 [2]          
Cost   2,430,904 [1]   2,430,904 [1]   1,787,824 [2]          
Borrowings under credit facilities   650,989   650,989   $ 655,189          
Total dividend income   7,905 2,867 22,844 3,333            
Distributions of realized gains by investment companies   $ 6,181 $ 0 $ 6,181 $ 0            
Number of members | member 2                    
Number of portfolio companies | investment   7   7   2          
Number of investments entered into | investment   21 19 69 59            
Investment, Identifier [Axis]: 1888 Industrial Services, LLC, Energy: Oil & Gas, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[5],[6],[7]   $ 0   $ 0              
Cost [3],[4],[5],[6],[7]   419   419              
Investment, Identifier [Axis]: 1888 Industrial Services, LLC, Energy: Oil & Gas, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[5],[6],[7]   1,171   1,171              
Cost [3],[4],[5],[6],[7]   1,423   1,423              
Investment, Identifier [Axis]: 1888 Industrial Services, LLC, Energy: Oil & Gas, Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: 1888 Industrial Services, LLC, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   $ 0          
Investment, Identifier [Axis]: 1888 Industrial Services, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   75   75   0          
Fair value of investment owned   1,171   1,171   0          
Investment, Identifier [Axis]: 1888 Industrial Services, LLC, Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: 1WorldSync, Inc., IT Consulting & Other Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           16,434          
Cost [9],[10],[11]           16,185          
Investment, Identifier [Axis]: 1WorldSync, Inc., IT Consulting & Other Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[12]   16,296   16,296              
Cost [3],[6],[12]   16,096   16,096              
Investment, Identifier [Axis]: ADB Safegate, Aerospace & Defense, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,620 [3],[6],[7],[13]   4,620 [3],[6],[7],[13]   5,106 [9],[11],[14]          
Cost   5,160 [3],[6],[7],[13]   5,160 [3],[6],[7],[13]   5,091 [9],[11],[14]          
Investment, Identifier [Axis]: AIT Worldwide Logistics Holdings, Inc., Transportation Services, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   787 [6],[8]   787 [6],[8]   689 [10]          
Cost   349 [6],[8]   349 [6],[8]   349 [10]          
Investment, Identifier [Axis]: AIT Worldwide Logistics Holdings, Inc., Transportation Services, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,350 [3],[6],[7]   6,350 [3],[6],[7]   6,460 [9],[10],[11]          
Cost   6,335 [3],[6],[7]   6,335 [3],[6],[7]   6,325 [9],[10],[11]          
Investment, Identifier [Axis]: AMMC CLO 22, Limited Series 2018-22A, Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   3,482   3,482              
Cost [4],[13]   4,469   4,469              
Investment, Identifier [Axis]: AMMC CLO 23, Ltd. Series 2020-23A, Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   1,552   1,552              
Cost [4],[13]   1,872   1,872              
Investment, Identifier [Axis]: AP Aristotle Holdings, LLC, Oil Field Services, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           1,854          
Cost [10]           1,890          
Investment, Identifier [Axis]: APC1 Holding, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   490   490   0          
Investment, Identifier [Axis]: APC1 Holding, Diversified Manufacturing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,701   1,701              
Cost [3],[6],[13],[15]   1,773   1,773              
Investment, Identifier [Axis]: APOG Bidco Pty Ltd, Healthcare, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[16]   1,962   1,962              
Cost [3],[6],[13],[16]   2,278   2,278              
Investment, Identifier [Axis]: AQA Acquisition Holding, Inc., High Tech Industries, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   19,730 [3],[6],[7]   19,730 [3],[6],[7]   20,000 [9],[10],[11]          
Cost   19,550 [3],[6],[7]   19,550 [3],[6],[7]   19,510 [9],[10],[11]          
Investment, Identifier [Axis]: ASC Communications, LLC, Media & Entertainment, Class A Units (25,718.20 units)                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   539   539              
Cost [6],[8]   539   539              
Investment, Identifier [Axis]: ASC Communications, LLC, Media & Entertainment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   21,447   21,447              
Cost [3],[6],[17]   21,460   21,460              
Investment, Identifier [Axis]: ASPEQ Heating Group LLC, Building Products, Air & Heating, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   8,363 [3],[6]   8,363 [3],[6]   8,464 [9],[10],[18]          
Cost   8,297 [3],[6]   8,297 [3],[6]   8,377 [9],[10],[18]          
Investment, Identifier [Axis]: AVSC Holding Corp., Advertising, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,223 [3],[7]   4,223 [3],[7]   4,458 [9],[11]          
Cost   4,479 [3],[7]   4,479 [3],[7]   4,405 [9],[11]          
Investment, Identifier [Axis]: AVSC Holding Corp., Advertising, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   660 [3],[7]   660 [3],[7]   693 [9],[11]          
Cost   701 [3],[7]   701 [3],[7]   693 [9],[11]          
Investment, Identifier [Axis]: AVSC Holding Corp., Advertising, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,012   6,012   6,404          
Cost   5,845   5,845   5,399          
Investment, Identifier [Axis]: Accelerant Holdings, Banking, Finance, Insurance & Real Estate, Class A Convertible Preferred Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   5,302   5,302              
Cost [6],[8]   5,000   5,000              
Investment, Identifier [Axis]: Accelerate Learning, Inc., Education Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,467 [3],[6],[7]   7,467 [3],[6],[7]   7,429 [9],[10],[11]          
Cost   7,505 [3],[6],[7]   7,505 [3],[6],[7]   7,486 [9],[10],[11]          
Investment, Identifier [Axis]: Acclime Holdings HK Limited , Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,179          
Investment, Identifier [Axis]: Acclime Holdings HK Limited , Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   110          
Investment, Identifier [Axis]: Acclime Holdings HK Limited, Business Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11],[14]           1,147          
Cost [9],[10],[11],[14]           1,138          
Investment, Identifier [Axis]: Acclime Holdings HK Limited, Business services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[19]   2,425   2,425              
Cost [3],[6],[13],[19]   2,441   2,441              
Investment, Identifier [Axis]: Accurus Aerospace Corporation, Aerospace & Defense, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   440   440              
Cost [6],[8]   438   438              
Investment, Identifier [Axis]: Accurus Aerospace Corporation, Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   12,153 [3],[6],[7]   12,153 [3],[6],[7]   24,016 [9],[10],[20]          
Cost   12,135 [3],[6],[7]   12,135 [3],[6],[7]   24,684 [9],[10],[20]          
Investment, Identifier [Axis]: Accurus Aerospace Corporation, Aerospace & Defense, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   (29)   (29)              
Cost [3],[6],[7]   (32)   (32)              
Investment, Identifier [Axis]: Accurus Aerospace Corporation, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,305   2,305   0          
Investment, Identifier [Axis]: Acogroup, Business Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   6,899   6,899              
Cost [3],[6],[13],[21]   7,703   7,703              
Investment, Identifier [Axis]: Advantage Insurance, Inc., Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned           0       $ 5,947  
Investment, Identifier [Axis]: Advantage Software Company (The), LLC, Advertising, Printing & Publishing, Class A1 Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   791 [6],[8]   791 [6],[8]   280 [10]          
Cost   280 [6],[8]   280 [6],[8]   280 [10]          
Investment, Identifier [Axis]: Advantage Software Company (The), LLC, Advertising, Printing & Publishing, Class A2 Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   204 [6],[8]   204 [6],[8]   72 [10]          
Cost   72 [6],[8]   72 [6],[8]   72 [10]          
Investment, Identifier [Axis]: Advantage Software Company (The), LLC, Advertising, Printing & Publishing, Class B1 Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   9 [10]          
Cost   9 [6],[8]   9 [6],[8]   9 [10]          
Investment, Identifier [Axis]: Advantage Software Company (The), LLC, Advertising, Printing & Publishing, Class B2 Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   2 [10]          
Cost   2 [6],[8]   2 [6],[8]   2 [10]          
Investment, Identifier [Axis]: Aftermath Bidco Corporation, Professional Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           9,303          
Cost [9],[10],[11]           9,299          
Investment, Identifier [Axis]: Air Canada 2020-2 Class B Pass Through Trust, Airlines, Structured Secured Note - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,395   5,395   6,822          
Cost   5,505   5,505   6,170          
Investment, Identifier [Axis]: Air Comm Corporation, LLC, Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   12,714 [3],[6],[7]   12,714 [3],[6],[7]   11,280 [9],[10],[11]          
Cost   12,692 [3],[6],[7]   12,692 [3],[6],[7]   11,265 [9],[10],[11]          
Investment, Identifier [Axis]: Air Comm Corporation, LLC, Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   11          
Investment, Identifier [Axis]: Air Comm Corporation, LLC, Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,448          
Investment, Identifier [Axis]: Alpine SG, LLC, High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[17]   22,765   22,765              
Cost [3],[4],[6],[17]   22,765   22,765              
Investment, Identifier [Axis]: Alpine US Bidco LLC, Agricultural Products, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   16,704 [3],[6],[22]   16,704 [3],[6],[22]   17,975 [9],[10],[11]          
Cost   17,679 [3],[6],[22]   17,679 [3],[6],[22]   17,642 [9],[10],[11]          
Investment, Identifier [Axis]: Amalfi Midco, Healthcare, Class B Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   1,040   1,040              
Cost [6],[8],[13]   1,040   1,040              
Investment, Identifier [Axis]: Amalfi Midco, Healthcare, Subordinated Loan Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   4,443   4,443              
Cost [6],[13]   4,451   4,451              
Investment, Identifier [Axis]: Amalfi Midco, Healthcare, Warrant                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   0   0              
Cost [6],[8],[13]   4   4              
Investment, Identifier [Axis]: Amtech LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,527   1,527   2,727          
Investment, Identifier [Axis]: Amtech LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   545   545   682          
Investment, Identifier [Axis]: Amtech LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,221 [3],[6],[22]   2,221 [3],[6],[22]   3,955 [9],[10],[18]          
Cost   2,208 [3],[6],[22]   2,208 [3],[6],[22]   3,958 [9],[10],[18]          
Investment, Identifier [Axis]: Amtech LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   127 [3],[6],[22]   127 [3],[6],[22]   (14) [9],[10],[11]          
Cost   125 [3],[6],[22]   125 [3],[6],[22]   (13) [9],[10],[11]          
Investment, Identifier [Axis]: Anagram Holdings, LLC, Chemicals, Plastics, & Rubber, First Lien Senior Secured Note                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   15,275   15,275   16,051 [14]          
Cost   14,338   14,338   13,459 [14]          
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Bridge Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   336   336   0          
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Chemicals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   2,135   2,135              
Cost [3],[6],[13],[15]   2,363   2,363              
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Chemicals, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   662   662              
Cost [3],[6],[13],[15]   789   789              
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Chemicals, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   5,134   5,134              
Cost [3],[6],[13],[15]   5,717   5,717              
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Chemicals, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7],[13]   996   996              
Cost [3],[6],[7],[13]   1,019   1,019              
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Chemicals, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   (8)   (8)              
Cost [3],[6],[13],[15]   (7)   (7)              
Investment, Identifier [Axis]: AnalytiChem Holding GmbH, Incremental Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   859   859   6,207          
Investment, Identifier [Axis]: AnalytiChem Holding Gmbh, Chemicals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           2,576          
Cost [9],[10],[14],[23]           2,580          
Investment, Identifier [Axis]: Anju Software, Inc., Application Software, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,437 [3],[6],[22]   11,437 [3],[6],[22]   13,284 [9],[10],[18]          
Cost   13,291 [3],[6],[22]   13,291 [3],[6],[22]   13,355 [9],[10],[18]          
Investment, Identifier [Axis]: Apex Bidco Limited, Business Equipment & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,627 [3],[6],[13]   1,627 [3],[6],[13]   1,970 [9],[10],[14],[24]          
Cost   1,874 [3],[6],[13]   1,874 [3],[6],[13]   1,869 [9],[10],[14],[24]          
Investment, Identifier [Axis]: Apex Bidco Limited, Business Equipment & Services, Subordinated Senior Unsecured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   243 [6],[13]   243 [6],[13]   278 [10],[14]          
Cost   280 [6],[13]   280 [6],[13]   264 [10],[14]          
Investment, Identifier [Axis]: Apidos CLO XXIV, Series 2016-24A, Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   6,498   6,498              
Cost [4],[13]   7,000   7,000              
Investment, Identifier [Axis]: Aptus 1829. GmbH, Chemicals, Plastics, & Rubber, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[14]           11          
Cost [10],[14]           12          
Investment, Identifier [Axis]: Aptus 1829. GmbH, Chemicals, Plastics, & Rubber, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           4,552          
Cost [9],[10],[14],[23]           4,717          
Investment, Identifier [Axis]: Aptus 1829. GmbH, Chemicals, Plastics, & Rubber, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[14]           111          
Cost [10],[14]           120          
Investment, Identifier [Axis]: Aptus 1829. GmbH, Chemicals, Plastics, and Rubber, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   13   13              
Cost [6],[8],[13]   12   12              
Investment, Identifier [Axis]: Aptus 1829. GmbH, Chemicals, Plastics, and Rubber, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   4,560   4,560              
Cost [3],[6],[13],[15]   5,462   5,462              
Investment, Identifier [Axis]: Aptus 1829. GmbH, Chemicals, Plastics, and Rubber, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   101   101              
Cost [6],[8],[13]   120   120              
Investment, Identifier [Axis]: Apus Bidco Limited, Banking, Finance, Insurance & Real Estate, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,142 [3],[6],[13],[25]   3,142 [3],[6],[13],[25]   3,823 [9],[10],[14],[26]          
Cost   3,883 [3],[6],[13],[25]   3,883 [3],[6],[13],[25]   3,874 [9],[10],[14],[26]          
Investment, Identifier [Axis]: Aquavista Watersides 2 LTD, Bridge Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   503          
Investment, Identifier [Axis]: Aquavista Watersides 2 LTD, Capex/Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,593   2,593   3,147          
Investment, Identifier [Axis]: Aquavista Watersides 2 LTD, Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,871 [3],[6],[13],[25]   4,871 [3],[6],[13],[25]   5,766 [9],[10],[14],[26]          
Cost   5,801 [3],[6],[13],[25]   5,801 [3],[6],[13],[25]   5,696 [9],[10],[14],[26]          
Investment, Identifier [Axis]: Aquavista Watersides 2 LTD, Transportation Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (56) [3],[6],[13],[25]   (56) [3],[6],[13],[25]   (5) [9],[10],[14],[26]          
Cost   (69) [3],[6],[13],[25]   (69) [3],[6],[13],[25]   (4) [9],[10],[14],[26]          
Investment, Identifier [Axis]: Aquavista Watersides 2 LTD, Transportation Services, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,285 [3],[6],[13],[25]   1,285 [3],[6],[13],[25]   1,465 [9],[10],[14],[26]          
Cost   1,527 [3],[6],[13],[25]   1,527 [3],[6],[13],[25]   1,446 [9],[10],[14],[26]          
Investment, Identifier [Axis]: Arc Education, Consumer Cyclical, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   2,707   2,707              
Cost [3],[6],[13],[15]   2,790   2,790              
Investment, Identifier [Axis]: Arc Education, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,744   1,744   0          
Investment, Identifier [Axis]: Arch Global Precision LLC, Industrial Machinery, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   9,133 [3],[6],[7]   9,133 [3],[6],[7]   9,248 [9],[10],[11]          
Cost   9,198 [3],[6],[7]   9,198 [3],[6],[7]   9,244 [9],[10],[11]          
Investment, Identifier [Axis]: Archimede, Consumer Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,635 [3],[6],[13],[21]   5,635 [3],[6],[13],[21]   8,255 [9],[10],[14],[23]          
Cost   6,468 [3],[6],[13],[21]   6,468 [3],[6],[13],[21]   8,761 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Argus Bidco Limited, Bridge Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   156   156   0          
Investment, Identifier [Axis]: Argus Bidco Limited, CAF Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   733   733   0          
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   1   1              
Cost [6],[8],[13]   1   1              
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, Equity Loan Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   46   46              
Cost [6],[13]   49   49              
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   126 [3],[6],[7],[13]   126 [3],[6],[7],[13]   2,682 [9],[10],[14],[27]          
Cost   126 [3],[6],[7],[13]   126 [3],[6],[7],[13]   2,559 [9],[10],[14],[27]          
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,418 [3],[6],[13],[28]   1,418 [3],[6],[13],[28]   672 [9],[10],[11],[14]          
Cost   1,512 [3],[6],[13],[28]   1,512 [3],[6],[13],[28]   653 [9],[10],[11],[14]          
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,416   1,416              
Cost [3],[6],[13],[15]   1,502   1,502              
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   46   46              
Cost [6],[13]   49   49              
Investment, Identifier [Axis]: Argus Bidco Limited, High Tech Industries, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   442   442              
Cost [6],[13]   469   469              
Investment, Identifier [Axis]: Armstrong Transport Group (Pele Buyer, LLC ), Air Freight & Logistics, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,938 [3],[6],[22]   3,938 [3],[6],[22]   3,939 [9],[10],[11]          
Cost   3,944 [3],[6],[22]   3,944 [3],[6],[22]   3,961 [9],[10],[11]          
Investment, Identifier [Axis]: Astra Bidco Limited, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   813   813   2,571          
Investment, Identifier [Axis]: Astra Bidco Limited, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,753 [3],[6],[13],[28]   1,753 [3],[6],[13],[28]   5,535 [9],[10],[14],[27]          
Cost   2,101 [3],[6],[13],[28]   2,101 [3],[6],[13],[28]   5,479 [9],[10],[14],[27]          
Investment, Identifier [Axis]: Auxi International, Commercial Finance, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,210 [3],[6],[13],[21]   1,210 [3],[6],[13],[21]   1,439 [9],[10],[14],[29]          
Cost   1,525 [3],[6],[13],[21]   1,525 [3],[6],[13],[21]   1,521 [9],[10],[14],[29]          
Investment, Identifier [Axis]: Auxi International, Commercial Finance, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   660 [3],[6],[13],[28]   660 [3],[6],[13],[28]   820 [9],[10],[14],[26]          
Cost   900 [3],[6],[13],[28]   900 [3],[6],[13],[28]   897 [9],[10],[14],[26]          
Investment, Identifier [Axis]: Avance Clinical Bidco Pty Ltd, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,228   1,228   3,497          
Investment, Identifier [Axis]: Avance Clinical Bidco Pty Ltd, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,195 [3],[6],[13],[30]   2,195 [3],[6],[13],[30]   6,158 [9],[10],[14],[31]          
Cost   2,413 [3],[6],[13],[30]   2,413 [3],[6],[13],[30]   6,040 [9],[10],[14],[31]          
Investment, Identifier [Axis]: Aviation Technical Services, Inc., Aerospace & Defense, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[22]   27,202   27,202              
Cost [3],[4],[6],[22]   26,701   26,701              
Investment, Identifier [Axis]: Azalea Buyer, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   961   961   962          
Investment, Identifier [Axis]: Azalea Buyer, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   481   481   481          
Investment, Identifier [Axis]: Azalea Buyer, Inc., Technology, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   143 [6],[8]   143 [6],[8]   192 [10]          
Cost   192 [6],[8]   192 [6],[8]   192 [10]          
Investment, Identifier [Axis]: Azalea Buyer, Inc., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,483 [3],[6],[7]   4,483 [3],[6],[7]   4,494 [10],[11]          
Cost   4,474 [3],[6],[7]   4,474 [3],[6],[7]   4,496 [10],[11]          
Investment, Identifier [Axis]: Azalea Buyer, Inc., Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (8) [3],[6],[7]   (8) [3],[6],[7]   (10) [10],[11]          
Cost   (8) [3],[6],[7]   (8) [3],[6],[7]   (9) [10],[11]          
Investment, Identifier [Axis]: Azalea Buyer, Inc., Technology, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,329 [6]   1,329 [6]   1,234 [10]          
Cost   1,326 [6]   1,326 [6]   1,235 [10]          
Investment, Identifier [Axis]: BDP International, Inc. (f/k/a BDP Buyer, LLC), Air Freight & Logistics, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[18]           14,626          
Cost [9],[10],[18]           14,643          
Investment, Identifier [Axis]: BVI Medical, Inc., Healthcare, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[15]   8,756   8,756              
Cost [3],[6],[15]   9,384   9,384              
Investment, Identifier [Axis]: Bariacum S.A, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,861   1,861   2,161          
Investment, Identifier [Axis]: Bariacum S.A, Consumer Products, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   5,439   5,439              
Cost [3],[6],[13],[15]   6,257   6,257              
Investment, Identifier [Axis]: Bariacum S.A, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,423   2,423   2,573          
Investment, Identifier [Axis]: Bariacum S.A., Consumer Products, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           6,244          
Cost [9],[10],[14],[23]           6,236          
Investment, Identifier [Axis]: Benify (Bennevis AB), High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   995 [3],[6],[13],[32]   995 [3],[6],[13],[32]   1,286 [9],[10],[14],[33]          
Cost   1,161 [3],[6],[13],[32]   1,161 [3],[6],[13],[32]   1,222 [9],[10],[14],[33]          
Investment, Identifier [Axis]: Beyond Risk Management, Inc., Other Financial, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,493 [3],[6],[7]   2,493 [3],[6],[7]   2,327 [9],[10],[11]          
Cost   2,498 [3],[6],[7]   2,498 [3],[6],[7]   2,336 [9],[10],[11]          
Investment, Identifier [Axis]: Bidwax, Non-durable Consumer Goods, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,659 [3],[6],[13],[21]   6,659 [3],[6],[13],[21]   7,741 [9],[10],[14],[23]          
Cost   8,082 [3],[6],[13],[21]   8,082 [3],[6],[13],[21]   8,062 [9],[10],[14],[23]          
Investment, Identifier [Axis]: BigHand UK Bidco Limited, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   378          
Investment, Identifier [Axis]: BigHand UK Bidco Limited, High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[34]           878          
Cost [9],[10],[14],[34]           880          
Investment, Identifier [Axis]: BigHand UK Bidco Limited, High Tech Industries, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[35]   2,491   2,491              
Cost [3],[6],[13],[35]   2,474   2,474              
Investment, Identifier [Axis]: BigHand UK Bidco Limited, High Tech Industries, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[28]   737   737              
Cost [3],[6],[13],[28]   892   892              
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   417   417   0          
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,647   5,647   0          
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   10,832   10,832   0          
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, Hotel, Gaming & Leisure, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[22]   5,647   5,647              
Cost [3],[4],[6],[22]   5,647   5,647              
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, Hotel, Gaming & Leisure, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[5],[6]   10,832   10,832              
Cost [4],[5],[6]   9,628   9,628              
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, Hotel, Gaming & Leisure, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: Black Angus Steakhouses, LLC, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Black Diamond Equipment Rentals LLC, Equipment Rental, Second Lien Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[36]           10,000          
Cost [10],[36]           10,000          
Investment, Identifier [Axis]: Black Diamond Equipment Rentals LLC, Equipment Rental, Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[36]           864          
Cost [10],[36]           1,010          
Investment, Identifier [Axis]: Bounteous, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,840   2,840   2,840          
Investment, Identifier [Axis]: Bounteous, Inc., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,823 [3],[6],[7]   1,823 [3],[6],[7]   4,756 [9],[10],[11]          
Cost   1,818 [3],[6],[7]   1,818 [3],[6],[7]   4,752 [9],[10],[11]          
Investment, Identifier [Axis]: Bridge Term Loan, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,089   1,089   0          
Investment, Identifier [Axis]: Bridger Aerospace Group Holdings, LLC, Environmental Industries, Municipal Revenue Bond                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   28,295   28,295              
Cost   27,200   27,200              
Investment, Identifier [Axis]: Bridger Aerospace Group Holdings, LLC, Environmental Industries, Preferred Stock- Series C                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   13,938   13,938              
Cost [6]   13,938   13,938              
Investment, Identifier [Axis]: BrightSign LLC, Media & Entertainment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,747 [3],[6],[7]   4,747 [3],[6],[7]   12,683 [9],[10],[11]          
Cost   4,739 [3],[6],[7]   4,739 [3],[6],[7]   12,687 [9],[10],[11]          
Investment, Identifier [Axis]: BrightSign LLC, Media & Entertainment, LLC units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,246 [6],[8]   1,246 [6],[8]   1,135 [10]          
Cost   1,107 [6],[8]   1,107 [6],[8]   1,107 [10]          
Investment, Identifier [Axis]: BrightSign LLC, Media & Entertainment, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (9) [3],[6],[7]   (9) [3],[6],[7]   (13) [9],[10],[11]          
Cost   (11) [3],[6],[7]   (11) [3],[6],[7]   (13) [9],[10],[11]          
Investment, Identifier [Axis]: BrightSign LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,329   1,329   1,329          
Investment, Identifier [Axis]: Brightline Trains Florida LLC, Transportation, Senior Secured Note                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,687 [6]   4,687 [6]   5,005 [10]          
Cost   5,000 [6]   5,000 [6]   5,000 [10]          
Investment, Identifier [Axis]: Brightpay Limited, Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   185   185   432          
Investment, Identifier [Axis]: Brightpay Limited, Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   124   124   144          
Investment, Identifier [Axis]: Brightpay Limited, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,806 [3],[6],[13],[15]   1,806 [3],[6],[13],[15]   1,862 [9],[10],[14],[23]          
Cost   2,110 [3],[6],[13],[15]   2,110 [3],[6],[13],[15]   1,883 [9],[10],[14],[23]          
Investment, Identifier [Axis]: British Airways 2020-1 Class B Pass Through Trust, Airlines, Structured Secured Note - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   741   741   916          
Cost   729   729   810          
Investment, Identifier [Axis]: British Engineering Services Holdco Limited, Bridge Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   613          
Investment, Identifier [Axis]: British Engineering Services Holdco Limited, Commercial Services & Supplies, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   12,452 [3],[6],[13],[25]   12,452 [3],[6],[13],[25]   15,406 [9],[10],[14],[26]          
Cost   15,120 [3],[6],[13],[25]   15,120 [3],[6],[13],[25]   15,081 [9],[10],[14],[26]          
Investment, Identifier [Axis]: British Engineering Services Holdco Limited, Commercial Services & Supplies, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[26]           (5)          
Cost [9],[10],[14],[26]           (2)          
Investment, Identifier [Axis]: Brook & Whittle Holding Corp., Containers, Packaging & Glass, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[22]   2,612   2,612              
Cost [3],[4],[6],[22]   2,819   2,819              
Investment, Identifier [Axis]: Brown Machine Group Holdings, LLC, Industrial Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,281 [3],[6],[7]   6,281 [3],[6],[7]   6,634 [9],[10],[18]          
Cost   6,248 [3],[6],[7]   6,248 [3],[6],[7]   6,587 [9],[10],[18]          
Investment, Identifier [Axis]: Burgess Point Purchaser Corporation, Auto Parts & Equipment, LP Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   410   410              
Cost [6],[8]   455   455              
Investment, Identifier [Axis]: Burgess Point Purchaser Corporation, Auto Parts & Equipment, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   4,364   4,364              
Cost [3],[6],[17]   4,366   4,366              
Investment, Identifier [Axis]: CAi Software, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   943   943   943          
Investment, Identifier [Axis]: CAi Software, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           8,876          
Cost [9],[10],[11]           8,877          
Investment, Identifier [Axis]: CAi Software, LLC, Technology, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   4,921   4,921              
Cost [3],[6],[7]   4,930   4,930              
Investment, Identifier [Axis]: CAi Software, LLC, Technology, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   1,353   1,353              
Cost [3],[6],[7]   1,354   1,354              
Investment, Identifier [Axis]: CAi Software, LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (19) [3],[6],[7]   (19) [3],[6],[7]   (19)          
Cost   (17) [3],[6],[7]   (17) [3],[6],[7]   (19)          
Investment, Identifier [Axis]: CGI Parent, LLC, Business Equipment & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   10,581   10,581              
Cost [3],[6],[7]   10,556   10,556              
Investment, Identifier [Axis]: CGI Parent, LLC, Business Equipment & Services, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   955   955              
Cost [6],[8]   551   551              
Investment, Identifier [Axis]: CGI Parent, LLC, Business Equipment & Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   (26)   (26)              
Cost [3],[6],[7]   (30)   (30)              
Investment, Identifier [Axis]: CGI Parent, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,653   1,653   0          
Investment, Identifier [Axis]: CM Acquisitions Holdings Inc., Internet & Direct Marketing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           19,106          
Cost [9],[10],[11]           18,897          
Investment, Identifier [Axis]: CM Acquisitions Holdings Inc., Internet & Direct Marketing, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   16,989   16,989              
Cost [3],[6],[35]   17,290   17,290              
Investment, Identifier [Axis]: CM Acquisitions Holdings Inc., Internet & Direct Marketing, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[37]   1,525   1,525              
Cost [3],[6],[37]   1,553   1,553              
Investment, Identifier [Axis]: CMT Opco Holding, LLC (Concept Machine), Distributors, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,969 [3],[6],[7]   3,969 [3],[6],[7]   3,999 [9],[10],[11]          
Cost   4,093 [3],[6],[7]   4,093 [3],[6],[7]   4,090 [9],[10],[11]          
Investment, Identifier [Axis]: CMT Opco Holding, LLC (Concept Machine), Distributors, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   159 [6]   159 [6]   227 [10]          
Cost   352 [6]   352 [6]   352 [10]          
Investment, Identifier [Axis]: CPI International, Inc., Aerospace & Defense, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[22]   8,318   8,318              
Cost [3],[4],[6],[22]   7,975   7,975              
Investment, Identifier [Axis]: CSL DualCom, Tele-communications, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,087 [3],[6],[13],[38]   1,087 [3],[6],[13],[38]   1,301 [9],[10],[14],[34]          
Cost   1,210 [3],[6],[13],[38]   1,210 [3],[6],[13],[38]   1,203 [9],[10],[14],[34]          
Investment, Identifier [Axis]: CSL Dualcom, Acquisition Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   822   822   998          
Investment, Identifier [Axis]: CT Technologies Intermediate Holdings, Inc., Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[22]   4,535   4,535              
Cost [3],[4],[22]   4,942   4,942              
Investment, Identifier [Axis]: CVL 3, Capital Equipment, 6-Month Bridge Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           788          
Cost [9],[10],[14],[23]           772          
Investment, Identifier [Axis]: CVL 3, Capital Equipment, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   816 [3],[6],[13],[15]   816 [3],[6],[13],[15]   5,766 [9],[10],[14],[23]          
Cost   938 [3],[6],[13],[15]   938 [3],[6],[13],[15]   5,724 [9],[10],[14],[23]          
Investment, Identifier [Axis]: CVL 3, Capital Equipment, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,119 [3],[6],[13],[35]   1,119 [3],[6],[13],[35]   3,298 [9],[10],[14],[39]          
Cost   1,116 [3],[6],[13],[35]   1,116 [3],[6],[13],[35]   3,298 [9],[10],[14],[39]          
Investment, Identifier [Axis]: CW Group Holdings, LLC, High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           2,774          
Cost [9],[10],[11]           2,762          
Investment, Identifier [Axis]: CW Group Holdings, LLC, High Tech Industries, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   102 [6],[8]   102 [6],[8]   112 [10]          
Cost   161 [6],[8]   161 [6],[8]   161 [10]          
Investment, Identifier [Axis]: CW Group Holdings, LLC, High Tech Industries,First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   2,722   2,722              
Cost [3],[6],[22]   2,755   2,755              
Investment, Identifier [Axis]: Cadent, LLC (f/k/a Cross MediaWorks), Media & Entertainment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,549 [3],[6],[7]   6,549 [3],[6],[7]   6,913 [9],[10],[18]          
Cost   6,737 [3],[6],[7]   6,737 [3],[6],[7]   6,888 [9],[10],[18]          
Investment, Identifier [Axis]: Cadent, LLC (f/k/a Cross MediaWorks), Media & Entertainment, First Lien Senior Secured Term Loan1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   11,082   11,082              
Cost [3],[6],[7]   11,143   11,143              
Investment, Identifier [Axis]: Canadian Orthodontic Partners Corp., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   109   109   167          
Investment, Identifier [Axis]: Canadian Orthodontic Partners Corp., Healthcare, Class A Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   364   364              
Cost [6],[8],[13]   389   389              
Investment, Identifier [Axis]: Canadian Orthodontic Partners Corp., Healthcare, Class C - Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   0   0              
Cost [6],[8],[13]   0   0              
Investment, Identifier [Axis]: Canadian Orthodontic Partners Corp., Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,476 [3],[6],[13],[40]   1,476 [3],[6],[13],[40]   1,625 [9],[10],[14],[41]          
Cost   1,730 [3],[6],[13],[40]   1,730 [3],[6],[13],[40]   1,697 [9],[10],[14],[41]          
Investment, Identifier [Axis]: Caribou Holding Company, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[35]   4,263   4,263              
Cost [3],[6],[13],[35]   4,258   4,258              
Investment, Identifier [Axis]: Caribou Holding Company, LLC, Technology, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[8],[13]   658   658              
Cost [3],[6],[8],[13]   682   682              
Investment, Identifier [Axis]: Carlson Travel, Inc, Business Travel Management, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,866 [8]   1,866 [8]   3,084          
Cost   4,194 [8]   4,194 [8]   1,655          
Investment, Identifier [Axis]: Carlson Travel, Inc, Business Travel Management, First Lien Senior Secured Note                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,203   5,203   6,161          
Cost   5,703   5,703   5,654          
Investment, Identifier [Axis]: Centralis Finco S.a.r.l., Diversified Financial Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,805 [3],[6],[13],[15]   1,805 [3],[6],[13],[15]   807 [9],[10],[14],[23]          
Cost   1,916 [3],[6],[13],[15]   1,916 [3],[6],[13],[15]   739 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Centralis Finco S.a.r.l., Incremental CAF Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   944   944   461          
Investment, Identifier [Axis]: Ceres Pharma NV, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,851   1,851   2,149          
Investment, Identifier [Axis]: Ceres Pharma NV, Pharma-ceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,119   1,119              
Cost [3],[6],[13],[15]   1,303   1,303              
Investment, Identifier [Axis]: Ceres Pharma NV, Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[29]           4,355          
Cost [9],[10],[14],[29]           4,444          
Investment, Identifier [Axis]: Charming Charlie LLC, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Charming Charlie LLC, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Charming Charlie LLC, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Charming Charlie LLC, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Charming Charlie LLC, First Lien Senior Secured Term Loan 4                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Charming Charlie LLC, Retail, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[5],[6],[8]   0   0              
Cost [4],[5],[6],[8]   0   0              
Investment, Identifier [Axis]: Charming Charlie LLC, Retail, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[5],[6]   0   0              
Cost [4],[5],[6]   0   0              
Investment, Identifier [Axis]: Charming Charlie LLC, Retail, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[5]   0   0              
Cost [4],[5]   0   0              
Investment, Identifier [Axis]: Charming Charlie LLC, Retail, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[5],[6],[7]   0   0              
Cost [3],[4],[5],[6],[7]   0   0              
Investment, Identifier [Axis]: Charming Charlie LLC, Retail, First Lien Senior Secured Term Loan 4                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[5],[6],[7]   0   0              
Cost [3],[4],[5],[6],[7]   0   0              
Investment, Identifier [Axis]: Cineworld Group PLC, Leisure Products, Super Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [14]           2,128          
Cost [14]           1,591          
Investment, Identifier [Axis]: Cineworld Group PLC, Leisure Products, Super Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[14],[20]           1,054          
Cost [9],[14],[20]           961          
Investment, Identifier [Axis]: Cineworld Group PLC, Leisure Products, Super Senior Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [13]   2,252   2,252              
Cost [13]   1,739   1,739              
Investment, Identifier [Axis]: Cineworld Group PLC, Leisure Products, Super Senior Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[13],[19]   1,061   1,061              
Cost [3],[13],[19]   970   970              
Investment, Identifier [Axis]: Cineworld Group PLC, Leisure Products, Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   41 [8],[13]   41 [8],[13]   244 [14]          
Cost   102 [8],[13]   102 [8],[13]   102 [14]          
Investment, Identifier [Axis]: Classic Collision (Summit Buyer, LLC), Auto Collision Repair Centers, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           12,448          
Cost [9],[10],[11]           12,384          
Investment, Identifier [Axis]: Classic Collision (Summit Buyer, LLC), Auto Collision Repair Centers, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   6,189   6,189              
Cost [3],[6],[19]   6,201   6,201              
Investment, Identifier [Axis]: Classic Collision (Summit Buyer, LLC), Auto Collision Repair Centers,First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   459   459              
Cost [3],[6],[19]   458   458              
Investment, Identifier [Axis]: Classic Collision (Summit Buyer, LLC), Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   141   141   393          
Investment, Identifier [Axis]: Coastal Marina Holdings, LLC, Other Financial, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   10,189 [6],[8]   10,189 [6],[8]   1,643 [10]          
Cost   9,093 [6],[8]   9,093 [6],[8]   1,643 [10]          
Investment, Identifier [Axis]: Coastal Marina Holdings, LLC, Other Financial, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           15,966          
Cost [10]           15,965          
Investment, Identifier [Axis]: Coastal Marina Holdings, LLC, Other Financial, Subordinated Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   4,678   4,678              
Cost [6]   4,735   4,735              
Investment, Identifier [Axis]: Coastal Marina Holdings, LLC, Other Financial, Subordinated Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   11,830   11,830              
Cost [6]   11,912   11,912              
Investment, Identifier [Axis]: Coastal Marina Holdings, LLC, PIK Tranche B Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,311   1,311   1,311          
Investment, Identifier [Axis]: Coastal Marina Holdings, LLC, Tranche A Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   3,576   3,576   3,576          
Investment, Identifier [Axis]: Cobham Slip Rings SAS, Diversified Manufacturing, Diversified Manufacturing                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7],[13]   1,267   1,267              
Cost [3],[6],[7],[13]   1,275   1,275              
Investment, Identifier [Axis]: Cobham Slip Rings SAS, Diversified Manufacturing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11],[14]           4,196          
Cost [9],[10],[11],[14]           4,199          
Investment, Identifier [Axis]: Command Alkon (Project Potter Buyer, LLC), Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   6,018          
Investment, Identifier [Axis]: Command Alkon (Project Potter Buyer, LLC), Software, , First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[18]           13,658          
Cost [9],[10],[18]           13,290          
Investment, Identifier [Axis]: Command Alkon (Project Potter Buyer, LLC), Software, Class A Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           101          
Cost [10]           90          
Investment, Identifier [Axis]: Command Alkon (Project Potter Buyer, LLC), Software, Class B Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   201   201              
Cost [6],[8]   0   0              
Investment, Identifier [Axis]: Command Alkon (Project Potter Buyer, LLC), Software, Class B Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           186          
Cost [10]           0          
Investment, Identifier [Axis]: Command Alkon (Project Potter Buyer, LLC), Software, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   13,342   13,342              
Cost [3],[6],[17]   13,336   13,336              
Investment, Identifier [Axis]: Compass Precision, LLC, Aerospace & Defense, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   129   129              
Cost [6],[8]   125   125              
Investment, Identifier [Axis]: Compass Precision, LLC, Aerospace & Defense, Senior Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   370   370              
Cost [6]   370   370              
Investment, Identifier [Axis]: Comply365, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,101   1,101   0          
Investment, Identifier [Axis]: Comply365, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   13,456   13,456              
Cost [3],[6],[35]   13,432   13,432              
Investment, Identifier [Axis]: Comply365, LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   (19)   (19)              
Cost [3],[6],[35]   (20)   (20)              
Investment, Identifier [Axis]: Contabo Finco S.À R.L, Internet Software & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,123 [3],[6],[13],[15]   5,123 [3],[6],[13],[15]   5,830 [9],[10],[14],[27]          
Cost   5,808 [3],[6],[13],[15]   5,808 [3],[6],[13],[15]   5,819 [9],[10],[14],[27]          
Investment, Identifier [Axis]: Core Scientific, Inc., Technology, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [8],[13]   119   119              
Cost [8],[13]   296   296              
Investment, Identifier [Axis]: Core Scientific, Inc., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   29,529   29,529              
Cost [6],[13]   29,619   29,619              
Investment, Identifier [Axis]: Coyo Uprising GmbH, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   770   770   894          
Investment, Identifier [Axis]: Coyo Uprising GmbH, Technology, Class A Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   178 [6],[8],[13]   178 [6],[8],[13]   587 [10],[14]          
Cost   205 [6],[8],[13]   205 [6],[8],[13]   205 [10],[14]          
Investment, Identifier [Axis]: Coyo Uprising GmbH, Technology, Class B Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   427 [6],[8],[13]   427 [6],[8],[13]   252 [10],[14]          
Cost   446 [6],[8],[13]   446 [6],[8],[13]   446 [10],[14]          
Investment, Identifier [Axis]: Coyo Uprising GmbH, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,548 [3],[6],[13],[21]   3,548 [3],[6],[13],[21]   3,938 [9],[10],[14],[23]          
Cost   4,217 [3],[6],[13],[21]   4,217 [3],[6],[13],[21]   4,050 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Crash Champions, Automotive, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           13,968          
Cost [9],[10],[11]           14,040          
Investment, Identifier [Axis]: Crash Champions, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   5,420          
Investment, Identifier [Axis]: Custom Alloy Corporation, Manufacturer of Pipe Fittings & Forgings, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   388 [5],[6],[42]   388 [5],[6],[42]   2,596 [10],[36],[43]          
Cost   4,222 [5],[6],[42]   4,222 [5],[6],[42]   3,738 [10],[36],[43]          
Investment, Identifier [Axis]: Custom Alloy Corporation, Manufacturer of Pipe Fittings & Forgings, Second Lien Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,107 [5],[6],[42]   4,107 [5],[6],[42]   27,450 [10],[36],[43]          
Cost   42,162 [5],[6],[42]   42,162 [5],[6],[42]   37,043 [10],[36],[43]          
Investment, Identifier [Axis]: Dart Buyer, Inc., Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11],[14]           11,734          
Cost [9],[10],[11],[14]           12,047          
Investment, Identifier [Axis]: Dart Buyer, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   2,431          
Investment, Identifier [Axis]: DataOnline Corp., High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   14,296   14,296              
Cost [3],[4],[6],[7]   14,588   14,588              
Investment, Identifier [Axis]: DataOnline Corp., High Tech Industries, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   2,100   2,100              
Cost [3],[4],[6],[7]   2,143   2,143              
Investment, Identifier [Axis]: DecksDirect, LLC, Building Materials, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   51   51              
Cost [6],[8]   55   55              
Investment, Identifier [Axis]: DecksDirect, LLC, Building Materials, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   690 [3],[6],[22]   690 [3],[6],[22]   713 [9],[10],[18]          
Cost   688 [3],[6],[22]   688 [3],[6],[22]   713 [9],[10],[18]          
Investment, Identifier [Axis]: DecksDirect, LLC, Building Materials, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           55          
Cost [10]           55          
Investment, Identifier [Axis]: DecksDirect, LLC, Building Materials, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (3) [3],[6],[22]   (3) [3],[6],[22]   (4) [9],[10],[11]          
Cost   (4) [3],[6],[22]   (4) [3],[6],[22]   (4) [9],[10],[11]          
Investment, Identifier [Axis]: DecksDirect, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   218   218   218          
Investment, Identifier [Axis]: Discovery Education, Inc., Publishing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           11,815          
Cost [9],[10],[11]           11,626          
Investment, Identifier [Axis]: Distinct Holdings, Inc., Systems Software, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,378 [3],[6],[7]   6,378 [3],[6],[7]   6,715 [9],[10],[18]          
Cost   6,855 [3],[6],[7]   6,855 [3],[6],[7]   6,841 [9],[10],[18]          
Investment, Identifier [Axis]: Dragon Bidco, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,359 [3],[6],[13],[21]   3,359 [3],[6],[13],[21]   2,676 [9],[10],[14],[29]          
Cost   3,995 [3],[6],[13],[21]   3,995 [3],[6],[13],[21]   2,812 [9],[10],[14],[29]          
Investment, Identifier [Axis]: DreamStart Bidco SAS (d/b/a SmartTrade), Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   531   531   617          
Investment, Identifier [Axis]: DreamStart Bidco SAS (d/b/a SmartTrade), Diversified Financial Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,073 [3],[6],[13],[15]   2,073 [3],[6],[13],[15]   2,385 [9],[10],[14],[29]          
Cost   2,302 [3],[6],[13],[15]   2,302 [3],[6],[13],[15]   2,295 [9],[10],[14],[29]          
Investment, Identifier [Axis]: Dryden 43 Senior Loan Fund, Series 2016-43A, Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   2,213   2,213              
Cost [4],[13]   2,347   2,347              
Investment, Identifier [Axis]: Dryden 49 Senior Loan Fund, Series 2017-49A, Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   5,334   5,334              
Cost [4],[13]   6,993   6,993              
Investment, Identifier [Axis]: Dune Group, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   573   573   665          
Investment, Identifier [Axis]: Dune Group, Health Care Equipment, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   105 [3],[6],[13],[15]   105 [3],[6],[13],[15]   1,202 [9],[10],[11],[14]          
Cost   108 [3],[6],[13],[15]   108 [3],[6],[13],[15]   1,205 [9],[10],[11],[14]          
Investment, Identifier [Axis]: Dune Group, Health Care Equipment, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,216 [3],[6],[7],[13]   1,216 [3],[6],[7],[13]   113 [9],[10],[14],[23]          
Cost   1,211 [3],[6],[7],[13]   1,211 [3],[6],[7],[13]   105 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Dunlipharder B.V., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[17]   987   987              
Cost [3],[6],[13],[17]   986   986              
Investment, Identifier [Axis]: Dwyer Instruments, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   5,164   5,164   692          
Investment, Identifier [Axis]: Dwyer Instruments, Inc., Electric, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           4,516          
Cost [9],[10],[11]           4,452          
Investment, Identifier [Axis]: Dwyer Instruments, Inc., Electric, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   678   678              
Cost [3],[6],[7]   686   686              
Investment, Identifier [Axis]: Dwyer Instruments, Inc., Electric, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   24,535   24,535              
Cost [3],[6],[7]   24,573   24,573              
Investment, Identifier [Axis]: EMI Porta Holdco LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   9,907   9,907   12,458          
Investment, Identifier [Axis]: EMI Porta Holdco LLC, Diversified Manufacturing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,470 [3],[6],[7]   11,470 [3],[6],[7]   9,136 [9],[10],[11]          
Cost   11,653 [3],[6],[7]   11,653 [3],[6],[7]   9,141 [9],[10],[11]          
Investment, Identifier [Axis]: EMI Porta Holdco LLC, Diversified Manufacturing, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   825 [3],[6],[7]   825 [3],[6],[7]   (59) [9],[10],[11]          
Cost   850 [3],[6],[7]   850 [3],[6],[7]   (59) [9],[10],[11]          
Investment, Identifier [Axis]: EMI Porta Holdco LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,064   2,064   2,966          
Investment, Identifier [Axis]: EPS NASS Parent, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   257   257   583          
Investment, Identifier [Axis]: EPS NASS Parent, Inc., Electrical Components & Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,028 [3],[6],[7]   6,028 [3],[6],[7]   5,715 [9],[10],[11]          
Cost   5,989 [3],[6],[7]   5,989 [3],[6],[7]   5,695 [9],[10],[11]          
Investment, Identifier [Axis]: Echo Global Logistics, Inc., Air Transportation, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   760 [6],[8]   760 [6],[8]   531 [10]          
Cost   531 [6],[8]   531 [6],[8]   531 [10]          
Investment, Identifier [Axis]: Echo Global Logistics, Inc., Air Transportation, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   9,081 [3],[6],[7]   9,081 [3],[6],[7]   14,216 [9],[10],[11]          
Cost   9,316 [3],[6],[7]   9,316 [3],[6],[7]   14,210 [9],[10],[11]          
Investment, Identifier [Axis]: Eclipse Business Capital Holdings LLC, Equity Investment                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned               $ 89,800      
Investment, Identifier [Axis]: Eclipse Business Capital Holdings LLC, Second Lien Senior Secured Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned               4,500      
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Banking, Finance, Insurance & Real Estate, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   126,568   126,568              
Cost [6]   89,850   89,850              
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Banking, Finance, Insurance & Real Estate, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[22]   6,182   6,182              
Cost [6],[22]   6,069   6,069              
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Banking, Finance, Insurance & Real Estate, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   4,545   4,545              
Cost [6]   4,506   4,506              
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Banking, Finance, Insurance, & Real Estate, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           92,668          
Cost [10]           89,850          
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Banking, Finance, Insurance, & Real Estate, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[11]           1,818          
Cost [10],[11]           1,691          
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Banking, Finance, Insurance, & Real Estate, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           4,738          
Cost [10]           4,502          
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, LLC units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   126,568   126,568   92,668       0  
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   16,545   16,545   11,818          
Fair value of investment owned   6,182   6,182   1,818       0  
Investment, Identifier [Axis]: Eclipse Business Capital, LLC, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,545   4,545   4,738       0  
Investment, Identifier [Axis]: Ellkay, LLC, Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           4,898          
Cost [9],[10],[11]           4,892          
Investment, Identifier [Axis]: Ellkay, LLC, Healthcare and Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   4,885   4,885              
Cost [3],[6],[7]   4,865   4,865              
Investment, Identifier [Axis]: Entact Environmental Services, Inc., Environmental Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,465 [3],[6],[7]   5,465 [3],[6],[7]   5,631 [9],[10],[11]          
Cost   5,544 [3],[6],[7]   5,544 [3],[6],[7]   5,657 [9],[10],[11]          
Investment, Identifier [Axis]: Eshipping, LLC, Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[18]           5,795          
Cost [9],[10],[18]           5,799          
Investment, Identifier [Axis]: Eshipping, LLC, Transportation Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           225          
Cost [9],[10],[11]           226          
Investment, Identifier [Axis]: Events Software BidCo Pty Ltd, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   640   640   0          
Investment, Identifier [Axis]: Events Software BidCo Pty Ltd, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[44]   1,549   1,549              
Cost [3],[6],[13],[44]   1,851   1,851              
Investment, Identifier [Axis]: Express Wash Acquisition Company, LLC, Consumer Cyclical, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   6,512   6,512              
Cost [3],[6],[17]   6,516   6,516              
Investment, Identifier [Axis]: Express Wash Acquisition Company, LLC, Consumer Cyclical, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   251   251              
Cost [3],[6],[17]   252   252              
Investment, Identifier [Axis]: Express Wash Acquisition Company, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   587   587   0          
Investment, Identifier [Axis]: F24 (Stairway BidCo GmbH), Acquisition Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   226   226   405          
Investment, Identifier [Axis]: F24 (Stairway BidCo Gmbh), Software Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,505 [3],[6],[13],[15]   1,505 [3],[6],[13],[15]   1,621 [9],[10],[14],[23]          
Cost   1,790 [3],[6],[13],[15]   1,790 [3],[6],[13],[15]   1,649 [9],[10],[14],[23]          
Investment, Identifier [Axis]: FSS Buyer LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,773 [3],[6],[22]   6,773 [3],[6],[22]   6,790 [9],[10],[11]          
Cost   6,741 [3],[6],[22]   6,741 [3],[6],[22]   6,773 [9],[10],[11]          
Investment, Identifier [Axis]: FSS Buyer LLC, Technology, LP Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   13 [6],[8]   13 [6],[8]   30 [10]          
Cost   12 [6],[8]   12 [6],[8]   12 [10]          
Investment, Identifier [Axis]: FSS Buyer LLC, Technology, LP Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   57 [6],[8]   57 [6],[8]   132 [10]          
Cost   51 [6],[8]   51 [6],[8]   51 [10]          
Investment, Identifier [Axis]: Ferrellgas L.P., Oil & Gas Equipment & Services, OpCo Preferred Units (2,886 units)                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[14]           3,146          
Cost [10],[14]           2,799          
Investment, Identifier [Axis]: Ferrellgas L.P., Oil & Gas Equipment & Services, Opco Preferred Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   2,742   2,742              
Cost [6]   2,799   2,799              
Investment, Identifier [Axis]: FinThrive Software Intermediate Holdings Inc., Business Equipment & Services, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   7,540   7,540              
Cost [6]   7,469   7,469              
Investment, Identifier [Axis]: Fineline Technologies, Inc., Consumer Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,281 [3],[6],[7]   1,281 [3],[6],[7]   1,306 [9],[10],[11]          
Cost   1,273 [3],[6],[7]   1,273 [3],[6],[7]   1,283 [9],[10],[11]          
Investment, Identifier [Axis]: Fineline Technologies, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   180   180   180          
Investment, Identifier [Axis]: Finexvet, Consumer Cyclical, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13]   2,138   2,138              
Cost [3],[6],[13]   2,377   2,377              
Investment, Identifier [Axis]: FitzMark Buyer, LLC, Cargo & Transportation, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,161 [3],[6],[7]   4,161 [3],[6],[7]   4,184 [9],[10],[11]          
Cost   4,164 [3],[6],[7]   4,164 [3],[6],[7]   4,197 [9],[10],[11]          
Investment, Identifier [Axis]: Five Star Holding LLC, Packaging, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   967   967              
Cost [6],[8]   967   967              
Investment, Identifier [Axis]: Five Star Holding LLC, Packaging, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   13,308   13,308              
Cost [3],[6],[17]   13,428   13,428              
Investment, Identifier [Axis]: Flexential Issuer, LLC, Information Technology, Structured Secured Note - Class C                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   13,773   13,773   15,609          
Cost   14,833   14,833   14,817          
Investment, Identifier [Axis]: Flywheel Re Segregated Portfolio 2022-4, Investment Funds, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   1,922   1,922              
Cost [6],[8],[13]   1,922   1,922              
Investment, Identifier [Axis]: Footco 40 Limited, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   711   711   0          
Investment, Identifier [Axis]: Footco 40 Limited, Media & Entertainment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[28]   1,334   1,334              
Cost [3],[6],[13],[28]   1,559   1,559              
Investment, Identifier [Axis]: FragilePak LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,354   2,354   2,354          
Investment, Identifier [Axis]: FragilePak LLC, Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,635 [3],[6],[7]   4,635 [3],[6],[7]   4,541 [9],[10],[18]          
Cost   4,495 [3],[6],[7]   4,495 [3],[6],[7]   4,519 [9],[10],[18]          
Investment, Identifier [Axis]: FragilePak LLC, Transportation Services, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,058 [6],[8]   1,058 [6],[8]   926          
Cost   938 [6],[8]   938 [6],[8]   938          
Investment, Identifier [Axis]: Front Line Power Construction LLC, Construction Machinery, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   91 [8]   91 [8]   111          
Cost   219 [8]   219 [8]   130          
Investment, Identifier [Axis]: Front Line Power Construction LLC, Construction Machinery, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,814 [3],[6],[7]   3,814 [3],[6],[7]   3,880 [9],[10],[11]          
Cost   3,791 [3],[6],[7]   3,791 [3],[6],[7]   3,872 [9],[10],[11]          
Investment, Identifier [Axis]: GPZN II GmbH, CAF Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   514   514   0          
Investment, Identifier [Axis]: GPZN II GmbH, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[45]   397   397              
Cost [3],[6],[13],[45]   428   428              
Investment, Identifier [Axis]: GTM Intermediate Holdings, Inc., Medical Equipment Manufacturer, Second Lien Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   10,518 [6],[42]   10,518 [6],[42]   11,500 [10],[36]          
Cost   10,559 [6],[42]   10,559 [6],[42]   11,449 [10],[36]          
Investment, Identifier [Axis]: GTM Intermediate Holdings, Inc., Medical Equipment Manufacturer, Series A Preferred Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,284 [6],[8],[42]   1,284 [6],[8],[42]   2,290 [10],[36]          
Cost   2,166 [6],[8],[42]   2,166 [6],[8],[42]   2,166 [10],[36]          
Investment, Identifier [Axis]: GTM Intermediate Holdings, Inc., Medical Equipment Manufacturer, Series C Preferred Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,632 [6],[8],[42]   1,632 [6],[8],[42]   1,184 [10],[36]          
Cost   1,081 [6],[8],[42]   1,081 [6],[8],[42]   1,081 [10],[36]          
Investment, Identifier [Axis]: Global Academic Group Limited, Industrial Other, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[44]   2,301   2,301              
Cost [3],[6],[13],[44]   2,499   2,499              
Investment, Identifier [Axis]: Global Academic Group Limited, Industrial Other, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[46]   3,775   3,775              
Cost [3],[6],[13],[46]   4,196   4,196              
Investment, Identifier [Axis]: Global Academic Group Limited, Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   403   403   0          
Investment, Identifier [Axis]: Greenhill II BV, Capex Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   234   234   0          
Investment, Identifier [Axis]: Greenhill II BV, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   653   653              
Cost [3],[6],[13],[15]   671   671              
Investment, Identifier [Axis]: Gulf Finance, LLC, Oil & Gas Exploration & Production, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   648 [3],[22]   648 [3],[22]   774 [9],[18]          
Cost   797 [3],[22]   797 [3],[22]   799 [9],[18]          
Investment, Identifier [Axis]: HTI Technology & Industries, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,045   2,045   0          
Investment, Identifier [Axis]: HTI Technology & Industries, Electronic Component Manufacturing, Second Lien Note                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,386 [3],[6],[35]   11,386 [3],[6],[35]   22,215 [10],[36]          
Cost   11,397 [3],[6],[35]   11,397 [3],[6],[35]   22,096 [10],[36]          
Investment, Identifier [Axis]: HTI Technology & Industries, Electronic Component Manufacturing, Second Lien Note1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   (20)   (20)              
Cost [3],[6],[35]   (19)   (19)              
Investment, Identifier [Axis]: HTI Technology & Industries, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,364   1,364   0          
Investment, Identifier [Axis]: HW Holdco, LLC (Hanley Wood LLC), Advertising, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   10,825 [3],[6],[7]   10,825 [3],[6],[7]   13,137 [9],[10],[18]          
Cost   10,844 [3],[6],[7]   10,844 [3],[6],[7]   13,189 [9],[10],[18]          
Investment, Identifier [Axis]: HW Holdco, LLC (Hanley Wood LLC), Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   913   913   1,563          
Investment, Identifier [Axis]: Hawaiian Airlines 2020-1 Class B Pass Through Certificates, Airlines, Structured Secured Note - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned           7,213          
Cost           6,093          
Investment, Identifier [Axis]: HeartHealth Bidco Pty Ltd, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   297   297   0          
Investment, Identifier [Axis]: HeartHealth Bidco Pty Ltd, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[44]   565   565              
Cost [3],[6],[13],[44]   568   568              
Investment, Identifier [Axis]: Heartland Veterinary Partners, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   267   267   657          
Investment, Identifier [Axis]: Heartland Veterinary Partners, LLC, Healthcare, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           9,093          
Cost [10]           9,096          
Investment, Identifier [Axis]: Heartland Veterinary Partners, LLC, Healthcare, Subordinated Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   1,163   1,163              
Cost [6]   1,159   1,159              
Investment, Identifier [Axis]: Heartland Veterinary Partners, LLC, Healthcare, Subordinated Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   9,261   9,261              
Cost [6]   9,233   9,233              
Investment, Identifier [Axis]: Heartland, LLC, Business Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   13,789 [3],[6],[7]   13,789 [3],[6],[7]   13,794 [9],[10],[11]          
Cost   13,891 [3],[6],[7]   13,891 [3],[6],[7]   13,976 [9],[10],[11]          
Investment, Identifier [Axis]: Heavy Construction Systems Specialists, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,632   2,632   2,632          
Investment, Identifier [Axis]: Heavy Construction Systems Specialists, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,264 [3],[6],[22]   7,264 [3],[6],[22]   7,221 [9],[10],[11]          
Cost   7,239 [3],[6],[22]   7,239 [3],[6],[22]   7,199 [9],[10],[11]          
Investment, Identifier [Axis]: Heavy Construction Systems Specialists, LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (37) [3],[6],[22]   (37) [3],[6],[22]   (53) [9],[10],[11]          
Cost   (45) [3],[6],[22]   (45) [3],[6],[22]   (54) [9],[10],[11]          
Investment, Identifier [Axis]: Heilbron (f/k/a Sucsez (Bolt Bidco B.V.)), Insurance, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,917 [3],[6],[13],[15]   2,917 [3],[6],[13],[15]   8,612 [9],[10],[14],[29]          
Cost   3,676 [3],[6],[13],[15]   3,676 [3],[6],[13],[15]   9,380 [9],[10],[14],[29]          
Investment, Identifier [Axis]: Highpoint Global LLC, Government Services, Second Lien Note                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[36]           5,416          
Cost [10],[36]           5,395          
Investment, Identifier [Axis]: Holland Acquisition Corp., Energy: Oil & Gas, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[5],[6],[19]   0   0              
Cost [3],[4],[5],[6],[19]   0   0              
Investment, Identifier [Axis]: Home Care Assistance, LLC, Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,737 [3],[6],[17]   3,737 [3],[6],[17]   3,753 [9],[10],[11]          
Cost   3,743 [3],[6],[17]   3,743 [3],[6],[17]   3,762 [9],[10],[11]          
Investment, Identifier [Axis]: Honour Lane Logistics Holdings Limited, Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[12],[13]   7,608   7,608              
Cost [3],[6],[12],[13]   7,724   7,724              
Investment, Identifier [Axis]: Hygie 31 Holding, Pharma-ceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,524   1,524              
Cost [3],[6],[13],[15]   1,497   1,497              
Investment, Identifier [Axis]: Hylan Datacom & Electrical LLC, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,220   4,220   0          
Investment, Identifier [Axis]: Hylan Datacom & Electrical LLC, Construction & Building, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   4,220   4,220              
Cost [6],[8]   5,219   5,219              
Investment, Identifier [Axis]: Hylan Datacom & Electrical LLC, Construction & Building, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   3,839   3,839              
Cost [3],[6],[35]   3,651   3,651              
Investment, Identifier [Axis]: Hylan Datacom & Electrical LLC, Construction & Building, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   3,902   3,902              
Cost [3],[6],[35]   3,982   3,982              
Investment, Identifier [Axis]: Hylan Datacom & Electrical LLC, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,839   3,839   0          
Investment, Identifier [Axis]: Hylan Datacom & Electrical LLC, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,902   3,902   0          
Investment, Identifier [Axis]: IGL Holdings III Corp., Commercial Printing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           4,268          
Cost [9],[10],[11]           4,231          
Investment, Identifier [Axis]: IGL Holdings III Corp., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,217          
Investment, Identifier [Axis]: IM Analytics Holding, LLC (d/b/a NVT), Electronic Instruments & Components, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,980 [3],[6],[7]   2,980 [3],[6],[7]   6,603 [9],[10],[11]          
Cost   3,402 [3],[6],[7]   3,402 [3],[6],[7]   8,085 [9],[10],[11]          
Investment, Identifier [Axis]: IM Analytics Holding, LLC (d/b/a NVT), Electronic Instruments & Components, Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   0 [9],[10]          
Cost   0 [6],[8]   0 [6],[8]   0 [9],[10]          
Investment, Identifier [Axis]: IM Square, Banking, Finance, Insurance & Real Estate, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,416 [3],[6],[13],[21]   2,416 [3],[6],[13],[21]   6,938 [9],[10],[14],[29]          
Cost   2,935 [3],[6],[13],[21]   2,935 [3],[6],[13],[21]   7,232 [9],[10],[14],[29]          
Investment, Identifier [Axis]: INOS 19-090 GmbH, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,184   2,184   2,535          
Investment, Identifier [Axis]: INOS 19-090 GmbH, Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,527 [3],[6],[13],[15]   4,527 [3],[6],[13],[15]   5,263 [9],[10],[14],[23]          
Cost   5,510 [3],[6],[13],[15]   5,510 [3],[6],[13],[15]   5,495 [9],[10],[14],[23]          
Investment, Identifier [Axis]: ISS#2, LLC (d/b/a Industrial Services Solutions), Commercial Services & Supplies, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,973 [3],[6],[7]   7,973 [3],[6],[7]   6,407 [9],[10],[11]          
Cost   8,060 [3],[6],[7]   8,060 [3],[6],[7]   6,639 [9],[10],[11]          
Investment, Identifier [Axis]: ITI Intermodal, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   103   103   103          
Investment, Identifier [Axis]: ITI Intermodal, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   118   118   124          
Investment, Identifier [Axis]: ITI Intermodal, Inc., Transportation Services, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   143   143              
Cost [6],[8]   144   144              
Investment, Identifier [Axis]: ITI Intermodal, Inc., Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   704 [3],[6],[22]   704 [3],[6],[22]   705 [9],[10],[18]          
Cost   701 [3],[6],[22]   701 [3],[6],[22]   705 [9],[10],[18]          
Investment, Identifier [Axis]: ITI Intermodal, Inc., Transportation Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4 [3],[6],[22]   4 [3],[6],[22]   (2) [9],[10],[11]          
Cost   4 [3],[6],[22]   4 [3],[6],[22]   (2) [9],[10],[11]          
Investment, Identifier [Axis]: Infoniqa Holdings GmbH, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,502 [3],[6],[13],[21]   2,502 [3],[6],[13],[21]   8,989 [9],[10],[14],[23]          
Cost   2,900 [3],[6],[13],[21]   2,900 [3],[6],[13],[21]   8,947 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Innovad Group II BV, Beverage, Food & Tobacco, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,183 [3],[6],[13],[21]   5,183 [3],[6],[13],[21]   5,876 [9],[10],[14],[23]          
Cost   6,785 [3],[6],[13],[21]   6,785 [3],[6],[13],[21]   6,321 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Innovad Group II BV, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,158   1,158   1,825          
Investment, Identifier [Axis]: Innovative XCessories & Services, LLC, Automotive, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[19]   2,356   2,356              
Cost [3],[4],[19]   2,870   2,870              
Investment, Identifier [Axis]: Interstellar Group B.V., Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,203   1,203   0          
Investment, Identifier [Axis]: Interstellar Group B.V., Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   109   109   0          
Investment, Identifier [Axis]: Interstellar Group B.V., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,084   1,084              
Cost [3],[6],[13],[15]   1,127   1,127              
Investment, Identifier [Axis]: Iqor US Inc., Services: Business, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[22]   2,669   2,669              
Cost [3],[4],[22]   2,725   2,725              
Investment, Identifier [Axis]: Isagenix International, LLC, Wholesale, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[5],[7]   625   625              
Cost [3],[4],[5],[7]   1,160   1,160              
Investment, Identifier [Axis]: Ivanti Software, Inc., High Tech Industries, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[7]   4,460   4,460              
Cost [3],[4],[7]   5,989   5,989              
Investment, Identifier [Axis]: JF Acquisition, LLC, Automotive, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,587 [3],[6],[22]   3,587 [3],[6],[22]   3,711 [9],[10],[11]          
Cost   3,751 [3],[6],[22]   3,751 [3],[6],[22]   3,763 [9],[10],[11]          
Investment, Identifier [Axis]: JSC Tekers Holdings, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0       0  
Investment, Identifier [Axis]: JSC Tekers Holdings, Common Stock, Controlled Investment                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: JSC Tekers Holdings, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   6,197       4,753  
Investment, Identifier [Axis]: JSC Tekers Holdings, Preferred Stock, Controlled Investment                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,862   5,862   0          
Investment, Identifier [Axis]: JSC Tekers Holdings, Real Estate Management, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8],[13],[42]   0 [6],[8],[13],[42]   0 [10],[14],[36]          
Cost   0 [6],[8],[13],[42]   0 [6],[8],[13],[42]   0 [10],[14],[36]          
Investment, Identifier [Axis]: JSC Tekers Holdings, Real Estate Management, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,862 [6],[8],[13],[42]   5,862 [6],[8],[13],[42]   6,197 [10],[14],[36]          
Cost   4,753 [6],[8],[13],[42]   4,753 [6],[8],[13],[42]   4,753 [10],[14],[36]          
Investment, Identifier [Axis]: Jade Bidco Limited (Jane's), Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[20]           2,315          
Cost [9],[10],[14],[20]           2,257          
Investment, Identifier [Axis]: Jade Bidco Limited (Jane's), Aerospace & Defense, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   3,672   3,672              
Cost [3],[6],[13],[21]   4,079   4,079              
Investment, Identifier [Axis]: Jade Bidco Limited (Jane's), Aerospace & Defense, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[19]   6,578   6,578              
Cost [3],[6],[13],[19]   6,571   6,571              
Investment, Identifier [Axis]: Jaguar Merger Sub Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   3,763   3,763   1,961          
Investment, Identifier [Axis]: Jaguar Merger Sub Inc., Other Financial, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,736 [3],[6],[35]   4,736 [3],[6],[35]   2,486 [9],[10],[11]          
Cost   4,768 [3],[6],[35]   4,768 [3],[6],[35]   2,487 [9],[10],[11]          
Investment, Identifier [Axis]: Jaguar Merger Sub Inc., Other Financial, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (7) [3],[6],[35]   (7) [3],[6],[35]   (6) [9],[10],[11]          
Cost   (4) [3],[6],[35]   (4) [3],[6],[35]   (6) [9],[10],[11]          
Investment, Identifier [Axis]: Jaguar Merger Sub Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   490   490   490          
Investment, Identifier [Axis]: Jedson Engineering, Inc., Engineering & Construction Management, First Lien Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,650 [6],[42]   2,650 [6],[42]   2,650 [10],[36]          
Cost   2,650 [6],[42]   2,650 [6],[42]   2,650 [10],[36]          
Investment, Identifier [Axis]: JetBlue 2019-1 Class B Pass Through Trust, Airlines, Structured Secured Note - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,815   3,815   4,805          
Cost   3,887   3,887   4,165          
Investment, Identifier [Axis]: Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   65,000   65,000   20,000          
Total contributed capital   35,000   35,000   30,000          
Investment, Identifier [Axis]: Jocassee Partners LLC, Investment Funds & Vehicles, 9.1% Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   40,845 [8],[13]   40,845 [8],[13]   37,601 [14]          
Cost   35,158 [8],[13]   35,158 [8],[13]   30,158 [14]          
Investment, Identifier [Axis]: Jocassee Partners LLC, Joint Venture                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   65,000   65,000   20,000          
Investment, Identifier [Axis]: Jocassee Partners LLC, Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   40,845   40,845   37,601       22,624  
Investment, Identifier [Axis]: Jon Bidco Limited, Capex & Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,289   1,289   0          
Investment, Identifier [Axis]: Jon Bidco Limited, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[46]   3,099   3,099              
Cost [3],[6],[13],[46]   3,807   3,807              
Investment, Identifier [Axis]: Jones Fish Hatcheries & Distributors LLC, Consumer Products, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   2,740   2,740              
Cost [3],[6],[22]   2,734   2,734              
Investment, Identifier [Axis]: Jones Fish Hatcheries & Distributors LLC, Consumer Products, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   97   97              
Cost [6],[8]   97   97              
Investment, Identifier [Axis]: Jones Fish Hatcheries & Distributors LLC, Consumer Products, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   (7)   (7)              
Cost [3],[6],[22]   (8)   (8)              
Investment, Identifier [Axis]: Jones Fish Hatcheries & Distributors LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   418   418   0          
Investment, Identifier [Axis]: Kano Laboratories LLC, Chemicals, Plastics & Rubber, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,546 [3],[6],[7]   5,546 [3],[6],[7]   8,728 [9],[10],[20]          
Cost   5,544 [3],[6],[7]   5,544 [3],[6],[7]   8,773 [9],[10],[20]          
Investment, Identifier [Axis]: Kano Laboratories LLC, Chemicals, Plastics & Rubber, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   192   192              
Cost [6],[8]   203   203              
Investment, Identifier [Axis]: Kano Laboratories LLC, Chemicals, Plastics & Rubber, Partnership Equity (203.2 units)                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           205          
Cost [10]           203          
Investment, Identifier [Axis]: Kano Laboratories LLC, Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   153   153   153          
Investment, Identifier [Axis]: Kano Laboratories LLC, Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,830   2,830   4,544          
Investment, Identifier [Axis]: Kemmerer Operations LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   908   908   0          
Investment, Identifier [Axis]: Kemmerer Operations, LLC, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,291   1,291   0          
Investment, Identifier [Axis]: Kemmerer Operations, LLC, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,379   2,379   0          
Investment, Identifier [Axis]: Kemmerer Operations, LLC, Metals & Mining, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   1,291   1,291              
Cost [4],[6],[8]   1,589   1,589              
Investment, Identifier [Axis]: Kemmerer Operations, LLC, Metals & Mining, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6]   2,379   2,379              
Cost [4],[6]   2,379   2,379              
Investment, Identifier [Axis]: Kene Acquisition, Inc. (En Engineering), Oil & Gas Equipment & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,041 [3],[6],[7]   7,041 [3],[6],[7]   7,080 [9],[10],[18]          
Cost   7,100 [3],[6],[7]   7,100 [3],[6],[7]   7,125 [9],[10],[18]          
Investment, Identifier [Axis]: Kid Distro Holdings, LLC, Media & Entertainment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   9,132 [3],[6],[7]   9,132 [3],[6],[7]   9,174 [9],[10],[11]          
Cost   9,096 [3],[6],[7]   9,096 [3],[6],[7]   9,168 [9],[10],[11]          
Investment, Identifier [Axis]: Kid Distro Holdings, LLC, Media & Entertainment, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   599   599              
Cost [6],[8]   638   638              
Investment, Identifier [Axis]: Kid Distro Holdings, LLC, Media & Entertainment, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned           638          
Cost           638          
Investment, Identifier [Axis]: Kona Buyer, LLC, High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   8,781 [3],[6],[7]   8,781 [3],[6],[7]   8,994 [9],[10],[11]          
Cost   8,779 [3],[6],[7]   8,779 [3],[6],[7]   8,785 [9],[10],[11]          
Investment, Identifier [Axis]: LAF International, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   341          
Investment, Identifier [Axis]: LAF International, Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[29]           1,446          
Cost [9],[10],[14],[29]           1,543          
Investment, Identifier [Axis]: Lambir Bidco Limited, Bridge Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   941          
Investment, Identifier [Axis]: Lambir Bidco Limited, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,621   1,621   1,881          
Investment, Identifier [Axis]: Lambir Bidco Limited, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,144 [3],[6],[13],[15]   4,144 [3],[6],[13],[15]   4,810 [9],[10],[14],[23]          
Cost   4,788 [3],[6],[13],[15]   4,788 [3],[6],[13],[15]   4,770 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Lambir Bidco Limited, Healthcare, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           295          
Cost [9],[10],[14],[23]           292          
Investment, Identifier [Axis]: Lambir Bidco Limited, Healthcare, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,246 [6],[13]   1,246 [6],[13]   1,375 [10],[14]          
Cost   1,446 [6],[13]   1,446 [6],[13]   1,363 [10],[14]          
Investment, Identifier [Axis]: Lattice Group Holdings Bidco Limited, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   298   298   0          
Investment, Identifier [Axis]: Lattice Group Holdings Bidco Limited, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[35]   646   646              
Cost [3],[6],[13],[35]   644   644              
Investment, Identifier [Axis]: Lattice Group Holdings Bidco Limited, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[35]   35   35              
Cost [3],[6],[13],[35]   35   35              
Investment, Identifier [Axis]: LeadsOnline, LLC, Business Equipment & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   10,160   10,160              
Cost [3],[6],[7]   10,138   10,138              
Investment, Identifier [Axis]: LeadsOnline, LLC, Business Equipment & Services, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   57   57              
Cost [6]   52   52              
Investment, Identifier [Axis]: LeadsOnline, LLC, Business Equipment & Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   (36)   (36)              
Cost [3],[6],[7]   (41)   (41)              
Investment, Identifier [Axis]: LeadsOnline, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,603   2,603   0          
Investment, Identifier [Axis]: Learfield Communications, LLC, Broadcasting, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   110 [3],[22]   110 [3],[22]   128 [9],[18]          
Cost   95 [3],[22]   95 [3],[22]   95 [9],[18]          
Investment, Identifier [Axis]: Learfield Communications, LLC, Broadcasting, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   8,500 [6],[7]   8,500 [6],[7]   7,959 [11]          
Cost   8,558 [6],[7]   8,558 [6],[7]   7,909 [11]          
Investment, Identifier [Axis]: Legal Solutions Holdings, Business Services, Senior Subordinated Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [5],[6],[42]   0 [5],[6],[42]   5,918 [10],[36],[43]          
Cost   10,129 [5],[6],[42]   10,129 [5],[6],[42]   10,129 [10],[36],[43]          
Investment, Identifier [Axis]: Liberty Steel Holdings USA Inc., Industrial Other, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   19,800   19,800              
Cost [3],[6],[17]   19,831   19,831              
Investment, Identifier [Axis]: Lifestyle Intermediate II, LLC, Consumer Goods: Durable, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   3,150   3,150              
Cost [3],[4],[6],[7]   3,214   3,214              
Investment, Identifier [Axis]: Lifestyle Intermediate II, LLC, Consumer Goods: Durable, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   (50)   (50)              
Cost [3],[4],[6],[7]   0   0              
Investment, Identifier [Axis]: Lifestyle Intermediate II, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,500   2,500   0          
Investment, Identifier [Axis]: LivTech Purchaser, Inc., Business Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   855 [3],[6],[7]   855 [3],[6],[7]   910 [9],[10],[11]          
Cost   855 [3],[6],[7]   855 [3],[6],[7]   908 [9],[10],[11]          
Investment, Identifier [Axis]: LivTech Purchaser, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   34   34   82          
Investment, Identifier [Axis]: LogMeIn, Inc., High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[22]   1,358   1,358              
Cost [3],[4],[22]   1,947   1,947              
Investment, Identifier [Axis]: Long Term Care Group, Inc., Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   7,926   7,926              
Cost [3],[6],[22]   7,911   7,911              
Investment, Identifier [Axis]: MC Group Ventures Corporation, Business Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,604 [3],[6],[7]   3,604 [3],[6],[7]   3,656 [9],[10],[11]          
Cost   3,581 [3],[6],[7]   3,581 [3],[6],[7]   3,598 [9],[10],[11]          
Investment, Identifier [Axis]: MC Group Ventures Corporation, Business Services, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   747 [6],[8]   747 [6],[8]   761 [10]          
Cost   747 [6],[8]   747 [6],[8]   747 [10]          
Investment, Identifier [Axis]: MC Group Ventures Corporation, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   817   817   817          
Investment, Identifier [Axis]: MNS Buyer, Inc., Construction & Building, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[18]           905          
Cost [9],[10],[18]           903          
Investment, Identifier [Axis]: MNS Buyer, Inc., Construction & Building, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           78          
Cost [10]           77          
Investment, Identifier [Axis]: MNS Buyer, Inc., Construction and Building, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   899   899              
Cost [3],[6],[22]   898   898              
Investment, Identifier [Axis]: MNS Buyer, Inc., Construction and Building, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   70   70              
Cost [6],[8]   77   77              
Investment, Identifier [Axis]: MSG National Properties, Hotel, Gaming, & Leisure, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11],[14]           2,486          
Cost [9],[10],[11],[14]           2,378          
Investment, Identifier [Axis]: MVC Automotive Group GmbH, Bridge Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,149   7,149   7,149       7,149  
Investment, Identifier [Axis]: MVC Automotive Group GmbH, Common Equity Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   9,498   9,498   7,699       9,582  
Investment, Identifier [Axis]: MVC Automotive Group Gmbh, Automotive, Bridge Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,149 [6],[13],[42]   7,149 [6],[13],[42]   7,149 [10],[14],[36]          
Cost   7,149 [6],[13],[42]   7,149 [6],[13],[42]   7,149 [10],[14],[36]          
Investment, Identifier [Axis]: MVC Automotive Group Gmbh, Automotive, Common Equity Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[14],[36]           7,699          
Cost [10],[14],[36]           9,553          
Investment, Identifier [Axis]: MVC Automotive Group Gmbh, Automotive, Common Equity interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13],[42]   9,498   9,498              
Cost [6],[8],[13],[42]   9,553   9,553              
Investment, Identifier [Axis]: MVC Private Equity Fund LP, General Partnership Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   41   41   188       225  
Investment, Identifier [Axis]: MVC Private Equity Fund LP, Investment Funds & Vehicles, General Partnership Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   41 [13],[42]   41 [13],[42]   188 [14],[36]          
Cost   225 [13],[42]   225 [13],[42]   225 [14],[36]          
Investment, Identifier [Axis]: MVC Private Equity Fund LP, Investment Funds & Vehicles, Limited Partnership Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,637 [13],[42]   1,637 [13],[42]   7,376 [14],[36]          
Cost   8,899 [13],[42]   8,899 [13],[42]   8,899 [14],[36]          
Investment, Identifier [Axis]: MVC Private Equity Fund LP, Limited Partnership Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,637   1,637   7,376       8,899  
Investment, Identifier [Axis]: Maccamaw River LLC, Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned           0       0  
Investment, Identifier [Axis]: Magnetite XIX, Limited, Multi-Sector Holdings, Subordinated Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[7],[13]   4,351   4,351              
Cost [4],[7],[13]   5,107   5,107              
Investment, Identifier [Axis]: Magnetite XIX, Limited, Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   7,742   7,742              
Cost [4],[13]   9,278   9,278              
Investment, Identifier [Axis]: Marmoutier Holding B.V., Consumer Products, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,961 [3],[6],[13],[15]   1,961 [3],[6],[13],[15]   1,880 [9],[10],[14],[23]          
Cost   2,217 [3],[6],[13],[15]   2,217 [3],[6],[13],[15]   1,872 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Marmoutier Holding B.V., Consumer Products, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (3) [3],[6],[13],[15]   (3) [3],[6],[13],[15]   (4) [9],[10],[14],[23]          
Cost   (4) [3],[6],[13],[15]   (4) [3],[6],[13],[15]   (4) [9],[10],[14],[23]          
Investment, Identifier [Axis]: Marmoutier Holding B.V., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   22   22   405          
Investment, Identifier [Axis]: Marmoutier Holding B.V., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   140   140   162          
Investment, Identifier [Axis]: Marshall Excelsior Co., Capital Goods, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   10,805   10,805              
Cost [3],[6],[35]   10,807   10,807              
Investment, Identifier [Axis]: Marshall Excelsior Co., Capital Goods, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   1,214   1,214              
Cost [3],[6],[35]   1,213   1,213              
Investment, Identifier [Axis]: Marshall Excelsior Co., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   413   413   0          
Investment, Identifier [Axis]: Media Recovery, Inc. (SpotSee), Containers, Packaging & Glass, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,911 [3],[6],[7]   2,911 [3],[6],[7]   2,933 [9],[10],[11]          
Cost   2,877 [3],[6],[7]   2,877 [3],[6],[7]   2,892 [9],[10],[11]          
Investment, Identifier [Axis]: Media Recovery, Inc. (SpotSee), Containers, Packaging & Glass, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,637 [3],[6],[38]   3,637 [3],[6],[38]   4,442 [9],[10],[24]          
Cost   4,283 [3],[6],[38]   4,283 [3],[6],[38]   4,303 [9],[10],[24]          
Investment, Identifier [Axis]: Median B.V., Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[25]   7,485   7,485              
Cost [3],[6],[13],[25]   9,785   9,785              
Investment, Identifier [Axis]: Medical Solutions Parent Holdings, Inc., Healthcare, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,200 [3],[6],[19]   4,200 [3],[6],[19]   4,362 [9],[11]          
Cost   4,381 [3],[6],[19]   4,381 [3],[6],[19]   4,377 [9],[11]          
Investment, Identifier [Axis]: Mercell Holding AS, Bridge Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   255   255   0          
Investment, Identifier [Axis]: Mercell Holding AS, Capex Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   850   850   0          
Investment, Identifier [Axis]: Mercell Holding AS, Technology, Class A Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   105   105              
Cost [6],[8],[13]   111   111              
Investment, Identifier [Axis]: Mercell Holding AS, Technology, Class B Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   0   0              
Cost [6],[8],[13]   0   0              
Investment, Identifier [Axis]: Mercell Holding AS, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[47]   3,286   3,286              
Cost [3],[6],[13],[47]   3,676   3,676              
Investment, Identifier [Axis]: Modern Star Holdings Bidco Pty Limited, Capex Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   918   918   1,038          
Investment, Identifier [Axis]: Modern Star Holdings Bidco Pty Limited., Non-durable Consumer Goods, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,217 [3],[6],[13],[16]   7,217 [3],[6],[13],[16]   8,299 [9],[10],[14],[48]          
Cost   8,313 [3],[6],[13],[16]   8,313 [3],[6],[13],[16]   8,281 [9],[10],[14],[48]          
Investment, Identifier [Axis]: Murphy Midco Limited, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   549   549   2,617          
Investment, Identifier [Axis]: Murphy Midco Limited, Media, Diversified & Production, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[34]           5,104          
Cost [9],[10],[14],[34]           4,951          
Investment, Identifier [Axis]: Murphy Midco Limited, Media, Diversified & Production, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[25]   767   767              
Cost [3],[6],[13],[25]   900   900              
Investment, Identifier [Axis]: Murphy Midco Limited, Media, Diversified & Production, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[25]   129   129              
Cost [3],[6],[13],[25]   152   152              
Investment, Identifier [Axis]: Music Reports, Inc., Media & Entertainment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,873 [3],[6],[22]   6,873 [3],[6],[22]   7,313 [9],[10],[11]          
Cost   6,875 [3],[6],[22]   6,875 [3],[6],[22]   7,288 [9],[10],[11]          
Investment, Identifier [Axis]: NGS US Finco, LLC (f/k/a Dresser Natural Gas Solutions), Energy Equipment & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,707 [3],[6],[22]   4,707 [3],[6],[22]   4,677 [9],[10],[18]          
Cost   4,705 [3],[6],[22]   4,705 [3],[6],[22]   4,734 [9],[10],[18]          
Investment, Identifier [Axis]: NPM Investments 28 B.V., Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,902   1,902              
Cost [3],[6],[13],[15]   1,902   1,902              
Investment, Identifier [Axis]: NPM Investments 28 BV, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   425   425   0          
Investment, Identifier [Axis]: Napa Bidco Pty Ltd, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[44]   17,049   17,049              
Cost [3],[6],[13],[44]   19,505   19,505              
Investment, Identifier [Axis]: Narda Acquisitionco., Inc., Aerospace & Defense, Class A Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   369 [6],[8]   369 [6],[8]   459 [10]          
Cost   459 [6],[8]   459 [6],[8]   459 [10]          
Investment, Identifier [Axis]: Narda Acquisitionco., Inc., Aerospace & Defense, Class B Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   51 [10]          
Cost   51 [6],[8]   51 [6],[8]   51 [10]          
Investment, Identifier [Axis]: Narda Acquisitionco., Inc., Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,229 [3],[6],[7]   5,229 [3],[6],[7]   5,580 [9],[10],[11]          
Cost   5,578 [3],[6],[7]   5,578 [3],[6],[7]   5,581 [9],[10],[11]          
Investment, Identifier [Axis]: Narda Acquisitionco., Inc., Aerospace & Defense, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (35) [3],[6],[7]   (35) [3],[6],[7]   (23) [9],[10],[11]          
Cost   46 [3],[6],[7]   46 [3],[6],[7]   (23) [9],[10],[11]          
Investment, Identifier [Axis]: Narda Acquisitionco., Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,245   1,245   1,311          
Investment, Identifier [Axis]: Navia Benefit Solutions, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,261          
Investment, Identifier [Axis]: Navia Benefit Solutions, Inc., Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,679 [3],[6],[22]   2,679 [3],[6],[22]   2,703 [9],[10],[11]          
Cost   2,667 [3],[6],[22]   2,667 [3],[6],[22]   2,668 [9],[10],[11]          
Investment, Identifier [Axis]: Nexus Underwriting Management Limited, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   411   411   541          
Investment, Identifier [Axis]: Nexus Underwriting Management Limited, Other Financial, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[25]   1,395   1,395              
Cost [3],[6],[13],[25]   1,682   1,682              
Investment, Identifier [Axis]: Nexus Underwriting Management Limited, Other Financial, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[26]           1,630          
Cost [9],[10],[14],[26]           1,620          
Investment, Identifier [Axis]: Nexus Underwriting Management Limited, Other Financial, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[26]           101          
Cost [9],[10],[14],[26]           102          
Investment, Identifier [Axis]: Nexus Underwriting Management Limited, Other Financial, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[25]   171   171              
Cost [3],[6],[13],[25]   202   202              
Investment, Identifier [Axis]: Nexus Underwriting Management Limited, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   103          
Investment, Identifier [Axis]: Northstar Recycling, LLC, Environmental Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,438 [3],[6],[7]   2,438 [3],[6],[7]   2,450 [9],[10],[11]          
Cost   2,439 [3],[6],[7]   2,439 [3],[6],[7]   2,452 [9],[10],[11]          
Investment, Identifier [Axis]: Novotech Aus Bidco Pty Ltd, Capex & Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   808   808   0          
Investment, Identifier [Axis]: Novotech Aus Bidco Pty Ltd, Healthcare, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[30]   3,173   3,173              
Cost [3],[6],[13],[30]   3,664   3,664              
Investment, Identifier [Axis]: Novotech Aus Bidco Pty Ltd, Healthcare, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[12],[13]   421   421              
Cost [3],[6],[12],[13]   448   448              
Investment, Identifier [Axis]: OA Buyer, Inc., Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,505 [3],[6],[22]   5,505 [3],[6],[22]   8,331 [9],[10],[11]          
Cost   5,499 [3],[6],[22]   5,499 [3],[6],[22]   8,331 [9],[10],[11]          
Investment, Identifier [Axis]: OA Buyer, Inc., Healthcare, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   211 [6],[8]   211 [6],[8]   211 [10]          
Cost   211 [6],[8]   211 [6],[8]   211 [10]          
Investment, Identifier [Axis]: OA Buyer, Inc., Healthcare, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (23) [3],[6],[22]   (23) [3],[6],[22]   (27) [9],[10],[11]          
Cost   (24) [3],[6],[22]   (24) [3],[6],[22]   (27) [9],[10],[11]          
Investment, Identifier [Axis]: OA Buyer, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,331   1,331   1,331          
Investment, Identifier [Axis]: OAC Holdings I Corp, Automotive, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   3,561   3,561              
Cost [3],[6],[35]   3,553   3,553              
Investment, Identifier [Axis]: OAC Holdings I Corp, Automotive, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   545   545              
Cost [3],[6],[35]   542   542              
Investment, Identifier [Axis]: OAC Holdings I Corp, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   802   802   0          
Investment, Identifier [Axis]: OG III B.V., Acquisition CapEx Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   686          
Investment, Identifier [Axis]: OG III B.V., Containers & Glass Products, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,088 [3],[6],[13],[15]   3,088 [3],[6],[13],[15]   2,843 [9],[10],[14],[23]          
Cost   3,671 [3],[6],[13],[15]   3,671 [3],[6],[13],[15]   2,997 [9],[10],[14],[23]          
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   187   187   187          
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,230 [3],[6],[7]   2,230 [3],[6],[7]   2,235 [9],[10],[18]          
Cost   2,223 [3],[6],[7]   2,223 [3],[6],[7]   2,235 [9],[10],[18]          
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, Technology, LP Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   67   67              
Cost [6],[8]   63   63              
Investment, Identifier [Axis]: OSP Hamilton Purchaser, LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (3) [3],[6],[7]   (3) [3],[6],[7]   (4) [9],[10],[11]          
Cost   (3) [3],[6],[7]   (3) [3],[6],[7]   (4) [9],[10],[11]          
Investment, Identifier [Axis]: Odeon Cinemas Group Limited, Hotel, Gaming, & Leisure, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,269 [13]   3,269 [13]   4,033 [10],[14]          
Cost   4,091 [13]   4,091 [13]   4,055 [10],[14]          
Investment, Identifier [Axis]: Offen Inc., Transportation: Cargo, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[19]   3,629   3,629              
Cost [4],[6],[19]   3,704   3,704              
Investment, Identifier [Axis]: Omni Intermediate Holdings, LLC, Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   817          
Investment, Identifier [Axis]: Omni Intermediate Holdings, LLC, Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,289   2,289   4,357          
Investment, Identifier [Axis]: Omni Intermediate Holdings, LLC, Transportation, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,996 [3],[6],[35]   5,996 [3],[6],[35]   11,491 [9],[10],[18]          
Cost   6,111 [3],[6],[35]   6,111 [3],[6],[35]   11,461 [9],[10],[18]          
Investment, Identifier [Axis]: Options Technology Ltd., Computer Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,264 [3],[6],[13],[19]   2,264 [3],[6],[13],[19]   2,267 [9],[10],[11],[14]          
Cost   2,270 [3],[6],[13],[19]   2,270 [3],[6],[13],[19]   2,282 [9],[10],[11],[14]          
Investment, Identifier [Axis]: Oracle Vision Bidco Limited, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,515 [3],[6],[13],[25]   2,515 [3],[6],[13],[25]   3,028 [9],[10],[14],[26]          
Cost   3,149 [3],[6],[13],[25]   3,149 [3],[6],[13],[25]   3,141 [9],[10],[14],[26]          
Investment, Identifier [Axis]: Origin Bidco Limited, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11],[14]           584          
Cost [9],[10],[11],[14]           582          
Investment, Identifier [Axis]: Origin Bidco Limited, Technology, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   318   318              
Cost [3],[6],[13],[15]   395   395              
Investment, Identifier [Axis]: Origin Bidco Limited, Technology, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7],[13]   584   584              
Cost [3],[6],[7],[13]   583   583              
Investment, Identifier [Axis]: Origin Bidco Limited, Technology, First Lien Senior Secured Term Loan1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           369          
Cost [9],[10],[14],[23]           394          
Investment, Identifier [Axis]: PDQ.Com Corporation, Business Equipment & Services, Class A-2 Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   38 [6],[8]   38 [6],[8]   29 [10]          
Cost   29 [6],[8]   29 [6],[8]   29 [10]          
Investment, Identifier [Axis]: PDQ.Com Corporation, Business Equipment & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,284 [3],[6],[7]   7,284 [3],[6],[7]   8,707 [9],[10],[11]          
Cost   7,243 [3],[6],[7]   7,243 [3],[6],[7]   8,710 [9],[10],[11]          
Investment, Identifier [Axis]: PDQ.Com Corporation, Delayed Draw Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   289          
Investment, Identifier [Axis]: PDQ.Com Corporation, Delayed Draw Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   7,753   7,753   10,948          
Investment, Identifier [Axis]: PSP Intermediate 4, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   667   667   0          
Investment, Identifier [Axis]: PSP Intermediate 4, LLC, Technology, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   766   766              
Cost [3],[6],[13],[15]   823   823              
Investment, Identifier [Axis]: PSP Intermediate 4, LLC, Technology, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7],[13]   845   845              
Cost [3],[6],[7],[13]   843   843              
Investment, Identifier [Axis]: Pacific Health Supplies Bidco Pty Limited, CapEx Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,283          
Investment, Identifier [Axis]: Pacific Health Supplies Bidco Pty Limited, Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[31]           8,529          
Cost [9],[10],[14],[31]           8,730          
Investment, Identifier [Axis]: Panoche Energy Center LLC, Electric, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   4,530   4,530              
Cost [6]   4,416   4,416              
Investment, Identifier [Axis]: Pare SAS (SAS Maurice MARLE), Health Care Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,989 [3],[6],[13],[21]   3,989 [3],[6],[13],[21]   4,638 [10],[14],[23]          
Cost   4,486 [3],[6],[13],[21]   4,486 [3],[6],[13],[21]   4,478 [10],[14],[23]          
Investment, Identifier [Axis]: Patriot New Midco 1 Limited (Forensic Risk Alliance), Diversified Financial Services, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,509 [3],[6],[13],[15]   2,509 [3],[6],[13],[15]   3,591 [9],[10],[11],[14]          
Cost   2,847 [3],[6],[13],[15]   2,847 [3],[6],[13],[15]   3,685 [9],[10],[11],[14]          
Investment, Identifier [Axis]: Patriot New Midco 1 Limited (Forensic Risk Alliance), Diversified Financial Services, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,408 [3],[6],[7],[13]   3,408 [3],[6],[7],[13]   3,068 [9],[10],[14],[23]          
Cost   3,477 [3],[6],[7],[13]   3,477 [3],[6],[7],[13]   3,017 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Credit Card ABS, Structured Secured Note - Class A                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   99   99              
Cost [6],[13]   109   109              
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Credit Card ABS, Structured Secured Note - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   98   98              
Cost [6],[13]   109   109              
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Credit Card ABS, Structured Secured Note - Class C                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   95   95              
Cost [6],[13]   109   109              
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Credit Card ABS, Structured Secured Note - Class D                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   94   94              
Cost [6],[13]   109   109              
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Credit Card ABS, Structured Secured Note - Class E                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   4,823   4,823              
Cost [6],[13]   5,564   5,564              
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Series 2022-One Class A                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   73   73   0          
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Series 2022-One Class B                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   73   73   0          
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Series 2022-One Class C                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   73   73   0          
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Series 2022-One Class D                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   73   73   0          
Investment, Identifier [Axis]: Perimeter Master Note Business Trust, Series 2022-One Class E                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   3,709   3,709   0          
Investment, Identifier [Axis]: Permaconn BidCo Pty Ltd, Tele-communications, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[44]   2,580   2,580              
Cost [3],[6],[13],[44]   2,862   2,862              
Investment, Identifier [Axis]: Permaconn Bidco Ltd, Tele-communications, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[48]           14,599          
Cost [9],[10],[14],[48]           14,386          
Investment, Identifier [Axis]: Polara Enterprises, L.L.C., Capital Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   1,211   1,211              
Cost [3],[6],[7]   1,212   1,212              
Investment, Identifier [Axis]: Polara Enterprises, L.L.C., Capital Equipment, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   741   741              
Cost [6],[8]   741   741              
Investment, Identifier [Axis]: Polara Enterprises, L.L.C., Capital Equipment, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   (10)   (10)              
Cost [3],[6],[7]   (9)   (9)              
Investment, Identifier [Axis]: Polara Enterprises, L.L.C., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   545   545   545          
Investment, Identifier [Axis]: Polara Enterprises, LLC, Capital Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           4,158          
Cost [9],[10],[11]           4,159          
Investment, Identifier [Axis]: Polara Enterprises, LLC, Capital Equipment, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           382          
Cost [10]           382          
Investment, Identifier [Axis]: Polara Enterprises, LLC, Capital Equipment, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           (11)          
Cost [9],[10],[11]           (11)          
Investment, Identifier [Axis]: Policy Services Company, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   6,944          
Investment, Identifier [Axis]: Policy Services Company, LLC, Property & Casualty Insurance, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   47,665 [3],[6],[7]   47,665 [3],[6],[7]   44,008 [9],[10],[11]          
Cost   47,920 [3],[6],[7]   47,920 [3],[6],[7]   44,018 [9],[10],[11]          
Investment, Identifier [Axis]: Policy Services Company, LLC, Property & Casualty Insurance, Warrants - Class A                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   0 [10]          
Cost   0 [6],[8]   0 [6],[8]   0 [10]          
Investment, Identifier [Axis]: Policy Services Company, LLC, Property & Casualty Insurance, Warrants - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   0 [10]          
Cost   0 [6],[8]   0 [6],[8]   0 [10]          
Investment, Identifier [Axis]: Policy Services Company, LLC, Property & Casualty Insurance, Warrants - Class C                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   0   0              
Cost [6],[8]   0   0              
Investment, Identifier [Axis]: Policy Services Company, LLC, Property & Casualty Insurance, Warrants - Class CC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           0          
Cost [10]           0          
Investment, Identifier [Axis]: Policy Services Company, LLC, Property & Casualty Insurance, Warrants - Class D                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[8]   0 [6],[8]   0 [10]          
Cost   0 [6],[8]   0 [6],[8]   0 [10]          
Investment, Identifier [Axis]: Polymer Solutions Group Holdings, LLC, Chemicals, Plastics & Rubber, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[22]   994   994              
Cost [3],[4],[6],[22]   1,014   1,014              
Investment, Identifier [Axis]: Premium Franchise Brands, LLC, Research & Consulting Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   12,521 [3],[6],[7]   12,521 [3],[6],[7]   14,556 [9],[10],[11]          
Cost   12,518 [3],[6],[7]   12,518 [3],[6],[7]   14,597 [9],[10],[11]          
Investment, Identifier [Axis]: Premium Invest, Brokerage, Asset Managers & Exchanges, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,192 [3],[6],[13],[21]   5,192 [3],[6],[13],[21]   4,010 [9],[10],[14],[23]          
Cost   5,796 [3],[6],[13],[21]   5,796 [3],[6],[13],[21]   4,113 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Premium Invest, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,645   2,645   1,933          
Investment, Identifier [Axis]: Preqin MC Limited, Banking, Finance, Insurance & Real Estate, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,738 [3],[6],[13]   2,738 [3],[6],[13]   2,764 [9],[10],[14],[36]          
Cost   2,717 [3],[6],[13]   2,717 [3],[6],[13]   2,695 [9],[10],[14],[36]          
Investment, Identifier [Axis]: Process Equipment, Inc. (ProcessBarron), Industrial Air & Material Handling Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,196 [3],[6],[35]   5,196 [3],[6],[35]   5,945 [9],[10],[11]          
Cost   5,644 [3],[6],[35]   5,644 [3],[6],[35]   6,115 [9],[10],[11]          
Investment, Identifier [Axis]: Process Equipment, Inc. (ProcessBarron), Industrial Air & Material Handling Equipment, First Lien Senior Secured Term Loan1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   310   310              
Cost [3],[6],[19]   336   336              
Investment, Identifier [Axis]: Professional Datasolutions, Inc. (PDI), Application Software, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,797 [3],[6],[7]   1,797 [3],[6],[7]   1,809 [9],[10],[11]          
Cost   1,821 [3],[6],[7]   1,821 [3],[6],[7]   1,833 [9],[10],[11]          
Investment, Identifier [Axis]: ProfitOptics, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   484   484   0          
Investment, Identifier [Axis]: ProfitOptics, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   1,727   1,727              
Cost [3],[6],[19]   1,737   1,737              
Investment, Identifier [Axis]: ProfitOptics, LLC, Technology, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   163   163              
Cost [6],[8]   161   161              
Investment, Identifier [Axis]: ProfitOptics, LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   (12)   (12)              
Cost [3],[6],[19]   (9)   (9)              
Investment, Identifier [Axis]: ProfitOptics, LLC, Technology, Second Lien Senior Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   79   79              
Cost [6]   81   81              
Investment, Identifier [Axis]: Proppants Holding, LLC, Energy: Oil & Gas, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: Protego Bidco B.V., Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   1,303   1,303              
Cost [3],[6],[13],[21]   1,567   1,567              
Investment, Identifier [Axis]: Protego Bidco B.V., Aerospace & Defense, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           2,195          
Cost [9],[10],[14],[23]           2,269          
Investment, Identifier [Axis]: Protego Bidco B.V., Aerospace & Defense, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           1,495          
Cost [9],[10],[14],[23]           1,561          
Investment, Identifier [Axis]: Protego Bidco B.V., Aerospace & Defense, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   1,900   1,900              
Cost [3],[6],[13],[15]   2,274   2,274              
Investment, Identifier [Axis]: Protego Bidco B.V., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   727   727   844          
Investment, Identifier [Axis]: QPE7 SPV1 BidCo Pty Ltd, Acquisition Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   373          
Investment, Identifier [Axis]: QPE7 SPV1 BidCo Pty Ltd, Consumer Cyclical, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,720 [3],[6],[13],[44]   1,720 [3],[6],[13],[44]   1,605 [9],[10],[14],[31]          
Cost   1,964 [3],[6],[13],[44]   1,964 [3],[6],[13],[44]   1,564 [9],[10],[14],[31]          
Investment, Identifier [Axis]: Questel Unite, Business Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,794 [3],[6],[7],[13]   6,794 [3],[6],[7],[13]   6,851 [9],[10],[11],[14]          
Cost   6,811 [3],[6],[7],[13]   6,811 [3],[6],[7],[13]   6,802 [9],[10],[11],[14]          
Investment, Identifier [Axis]: RA Outdoors, LLC, High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   12,659   12,659              
Cost [3],[4],[6],[7]   12,658   12,658              
Investment, Identifier [Axis]: RA Outdoors, LLC, High Tech Industries, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   (25)   (25)              
Cost [3],[4],[6],[7]   0   0              
Investment, Identifier [Axis]: RA Outdoors, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,235   1,235   0          
Investment, Identifier [Axis]: REP SEKO MERGER SUB LLC, Air Freight & Logistics, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           7,478          
Cost [9],[10],[11]           7,416          
Investment, Identifier [Axis]: REP SEKO MERGER SUB LLC, Air Freight & Logistics, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[21]   8,696   8,696              
Cost [3],[6],[21]   9,282   9,282              
Investment, Identifier [Axis]: REP SEKO MERGER SUB LLC, Air Freight & Logistics, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   1,069   1,069              
Cost [3],[6],[7]   1,059   1,059              
Investment, Identifier [Axis]: RPX Corporation, Research & Consulting Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,229 [3],[6],[22]   7,229 [3],[6],[22]   7,455 [9],[10],[11]          
Cost   7,213 [3],[6],[22]   7,213 [3],[6],[22]   7,426 [9],[10],[11]          
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Consumer Goods: Durable, Class A Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6]   1   1              
Cost [4],[6]   4   4              
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Consumer Goods: Durable, Class B Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Consumer Goods: Durable, Class C Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   217   217              
Cost [4],[6],[8]   450   450              
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Consumer Goods: Durable, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Consumer Goods: Durable, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   10,013   10,013              
Cost [3],[4],[6],[7]   10,166   10,166              
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Consumer Goods: Durable, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   2,877   2,877              
Cost [3],[4],[6],[7]   2,936   2,936              
Investment, Identifier [Axis]: RTIC Subsidiary Holdings, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,032   1,032   0          
Investment, Identifier [Axis]: Recovery Point Systems, Inc., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,566 [3],[6],[7]   11,566 [3],[6],[7]   11,648 [9],[10],[11]          
Cost   11,428 [3],[6],[7]   11,428 [3],[6],[7]   11,460 [9],[10],[11]          
Investment, Identifier [Axis]: Recovery Point Systems, Inc., Technology, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   125 [6],[8]   125 [6],[8]   150 [10]          
Cost   187 [6],[8]   187 [6],[8]   187 [10]          
Investment, Identifier [Axis]: Renovation Parent Holdings, LLC, Home Furnishings, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[20]           4,733          
Cost [9],[10],[20]           4,735          
Investment, Identifier [Axis]: Renovation Parent Holdings, LLC, Home Furnishings, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10]           203          
Cost [10]           197          
Investment, Identifier [Axis]: Renovation Parent Holdings, LLC, Home furnishings, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   4,733   4,733              
Cost [3],[6],[7]   4,713   4,713              
Investment, Identifier [Axis]: Renovation Parent Holdings, LLC, Home furnishings, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   197   197              
Cost [6],[8]   197   197              
Investment, Identifier [Axis]: Rep Seko Merger Sub LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   929   929   1,455          
Investment, Identifier [Axis]: Resolute Investment Managers, Inc., Banking, Finance, Insurance & Real Estate, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   4,624   4,624              
Cost [3],[4],[6],[7]   5,107   5,107              
Investment, Identifier [Axis]: Resonetics, LLC, Health Care Equipment, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,954 [3],[6],[7]   3,954 [3],[6],[7]   3,930 [9],[10],[11]          
Cost   3,940 [3],[6],[7]   3,940 [3],[6],[7]   3,934 [9],[10],[11]          
Investment, Identifier [Axis]: Reward Gateway (UK) Ltd, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   557   557   1,061          
Investment, Identifier [Axis]: Reward Gateway (UK) Ltd, Precious Metals & Minerals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,628 [3],[6],[13],[28]   2,628 [3],[6],[13],[28]   2,776 [9],[10],[14],[26]          
Cost   3,227 [3],[6],[13],[28]   3,227 [3],[6],[13],[28]   2,807 [9],[10],[14],[26]          
Investment, Identifier [Axis]: Riedel Beheer B.V., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   153          
Investment, Identifier [Axis]: Riedel Beheer B.V., Food & Beverage, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,976 [3],[6],[13],[15]   1,976 [3],[6],[13],[15]   1,843 [9],[10],[14],[23]          
Cost   2,246 [3],[6],[13],[15]   2,246 [3],[6],[13],[15]   1,835 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Riedel Beheer B.V., Food & Beverage, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           (5)          
Cost [9],[10],[14],[23]           (5)          
Investment, Identifier [Axis]: Riedel Beheer B.V., Food & Beverage, Super Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[14],[23]           223          
Cost [9],[10],[14],[23]           222          
Investment, Identifier [Axis]: Riedel Beheer B.V., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   230          
Investment, Identifier [Axis]: Royal Buyer, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,209   2,209   0          
Investment, Identifier [Axis]: Royal Buyer, LLC, Industrial Other, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   10,779   10,779              
Cost [3],[6],[35]   10,782   10,782              
Investment, Identifier [Axis]: Royal Buyer, LLC, Industrial Other, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   373   373              
Cost [3],[6],[35]   373   373              
Investment, Identifier [Axis]: Royal Buyer, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,340   1,340   0          
Investment, Identifier [Axis]: Ruffalo Noel Levitz, LLC, Media Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   9,445 [3],[6],[7]   9,445 [3],[6],[7]   9,543 [9],[10],[11]          
Cost   9,445 [3],[6],[7]   9,445 [3],[6],[7]   9,524 [9],[10],[11]          
Investment, Identifier [Axis]: SISU ACQUISITIONCO., INC., Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,396 [3],[6],[7]   6,396 [3],[6],[7]   6,771 [9],[10],[11]          
Cost   6,867 [3],[6],[7]   6,867 [3],[6],[7]   6,869 [9],[10],[11]          
Investment, Identifier [Axis]: SMART Financial Operations, LLC, Banking, Finance, Insurance & Real Estate, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   110   110              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: SN BUYER, LLC, Health Care Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,130 [3],[6],[22]   11,130 [3],[6],[22]   18,394 [9],[10],[18]          
Cost   10,964 [3],[6],[22]   10,964 [3],[6],[22]   18,080 [9],[10],[18]          
Investment, Identifier [Axis]: SPT Acquico Limited, High Tech Industries, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11],[14]           658          
Cost [9],[10],[11],[14]           644          
Investment, Identifier [Axis]: SSCP Pegasus Midco Limited, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   4,328   4,328   5,251          
Investment, Identifier [Axis]: SSCP Pegasus Midco Limited, Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,195 [3],[6],[13],[28]   2,195 [3],[6],[13],[28]   2,722 [9],[10],[14],[24]          
Cost   2,559 [3],[6],[13],[28]   2,559 [3],[6],[13],[28]   2,488 [9],[10],[14],[24]          
Investment, Identifier [Axis]: Safety Products Holdings, LLC, Non-durable Consumer Goods, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,813 [3],[6],[22]   11,813 [3],[6],[22]   11,755 [9],[10],[18]          
Cost   11,795 [3],[6],[22]   11,795 [3],[6],[22]   11,798 [9],[10],[18]          
Investment, Identifier [Axis]: Safety Products Holdings, LLC, Non-durable Consumer Goods, Preferred Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   507 [6],[8]   507 [6],[8]   510 [10]          
Cost   372 [6],[8]   372 [6],[8]   372 [10]          
Investment, Identifier [Axis]: Sanoptis S.A.R.L., Acquisition Capex Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,126   2,126   0          
Investment, Identifier [Axis]: Sanoptis S.A.R.L., Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   1,819   1,819              
Cost [3],[6],[13],[21]   1,807   1,807              
Investment, Identifier [Axis]: Sanoptis S.A.R.L., Healthcare & Pharmaceuticals, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[49]   3,072   3,072              
Cost [3],[6],[13],[49]   3,134   3,134              
Investment, Identifier [Axis]: Scaled Agile, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   416   416   416          
Investment, Identifier [Axis]: Scaled Agile, Inc., Research & Consulting Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,739 [3],[6],[35]   1,739 [3],[6],[35]   1,705 [9],[10],[11]          
Cost   1,703 [3],[6],[35]   1,703 [3],[6],[35]   1,705 [9],[10],[11]          
Investment, Identifier [Axis]: Scaled Agile, Inc., Research & Consulting Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [3],[6],[35]   0 [3],[6],[35]   (7) [9],[10],[11]          
Cost   (6) [3],[6],[35]   (6) [3],[6],[35]   (7) [9],[10],[11]          
Investment, Identifier [Axis]: Scaled Agile, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   336   336   336          
Investment, Identifier [Axis]: Scout Bidco B.V., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,083   2,083   0          
Investment, Identifier [Axis]: Scout Bidco B.V., Diversified Manufacturing, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   5,775   5,775              
Cost [3],[6],[13],[15]   6,279   6,279              
Investment, Identifier [Axis]: Scout Bidco B.V., Diversified Manufacturing, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[15]   (21)   (21)              
Cost [3],[6],[13],[15]   (25)   (25)              
Investment, Identifier [Axis]: Scout Bidco B.V., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   945   945   0          
Investment, Identifier [Axis]: Security Holdings B.V, Bridge Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   5,451       5,188  
Investment, Identifier [Axis]: Security Holdings B.V, Bridge Loan, Controlled                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,871   5,871   0          
Investment, Identifier [Axis]: Security Holdings B.V, Common Equity Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   24,825       21,329  
Investment, Identifier [Axis]: Security Holdings B.V, Common Stock Series A, Controlled                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   608   608   0          
Investment, Identifier [Axis]: Security Holdings B.V, Common Stock Series B, Controlled                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   56,808   56,808   0          
Investment, Identifier [Axis]: Security Holdings B.V, Senior Subordinated Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   9,525       8,746  
Investment, Identifier [Axis]: Security Holdings B.V, Senior Subordinated Note, Controlled                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   0          
Investment, Identifier [Axis]: Security Holdings B.V, Senior Subordinated Term Loan, Controlled                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   10,513   10,513   0          
Investment, Identifier [Axis]: Security Holdings B.V, Senior Unsecured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0   0   7,307       0  
Investment, Identifier [Axis]: Security Holdings B.V, Senior Unsecured Term Loan, Controlled                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,660   2,660   0          
Investment, Identifier [Axis]: Security Holdings B.V., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,959   1,959   2,274          
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Bridge Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,871 [6],[13],[42]   5,871 [6],[13],[42]   5,451 [10],[14],[36]          
Cost   5,871 [6],[13],[42]   5,871 [6],[13],[42]   5,451 [10],[14],[36]          
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[14],[36]           24,825          
Cost [10],[14],[36]           21,264          
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Common Stock Series A                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13],[42]   608   608              
Cost [6],[8],[13],[42]   560   560              
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Common Stock Series B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13],[42]   56,808   56,808              
Cost [6],[8],[13],[42]   35,192   35,192              
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Senior Subordinated Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [10],[14],[36]           9,525          
Cost [10],[14],[36]           9,525          
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Senior Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13],[42]   10,513   10,513              
Cost [6],[13],[42]   10,513   10,513              
Investment, Identifier [Axis]: Security Holdings B.V., Electrical Engineering, Senior Unsecured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,660 [6],[13],[42]   2,660 [6],[13],[42]   7,307 [10],[14],[36]          
Cost   3,172 [6],[13],[42]   3,172 [6],[13],[42]   7,639 [10],[14],[36]          
Investment, Identifier [Axis]: Security Holdings B.V., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   980   980   1,137          
Investment, Identifier [Axis]: Sereni Capital NV, Consumer Cyclical, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   198   198              
Cost [3],[6],[13],[21]   200   200              
Investment, Identifier [Axis]: Sereni Capital NV, Consumer Cyclical, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   439   439              
Cost [3],[6],[13],[21]   479   479              
Investment, Identifier [Axis]: Sereni Capital NV, Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   220   220   0          
Investment, Identifier [Axis]: Serta Simmons Bedding LLC, Home Furnishings, Super Priority First Out                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,057 [3],[7]   7,057 [3],[7]   7,409 [9],[18]          
Cost   7,228 [3],[7]   7,228 [3],[7]   7,229 [9],[18]          
Investment, Identifier [Axis]: Serta Simmons Bedding LLC, Home Furnishings, Super Priority Second Out                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,866 [3],[7]   1,866 [3],[7]   3,365 [9],[18]          
Cost   3,372 [3],[7]   3,372 [3],[7]   3,374 [9],[18]          
Investment, Identifier [Axis]: Sierra Senior Loan Strategy JV I LLC, Joint Venture, 89.01% Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   40,216   40,216              
Cost [4],[13]   50,221   50,221              
Investment, Identifier [Axis]: Sierra Senior Loan Strategy JV I LLC, Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   40,216   40,216   0          
Investment, Identifier [Axis]: Sierra Senior Loan Strategy JV LLC (Sierra JV)                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital   110,100   110,100              
Investment, Identifier [Axis]: Smartling, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,978   1,978   2,353          
Investment, Identifier [Axis]: Smartling, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,176   1,176   1,176          
Investment, Identifier [Axis]: Smartling, Inc., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   13,475 [3],[6],[7]   13,475 [3],[6],[7]   16,094 [9],[10],[11]          
Cost   13,467 [3],[6],[7]   13,467 [3],[6],[7]   16,102 [9],[10],[11]          
Investment, Identifier [Axis]: Smartling, Inc., Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (20) [3],[6],[7]   (20) [3],[6],[7]   (24) [9],[10],[11]          
Cost   (20) [3],[6],[7]   (20) [3],[6],[7]   (23) [9],[10],[11]          
Investment, Identifier [Axis]: Smile Brands Group Inc., Health Care Services, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   600 [3],[6],[19]   600 [3],[6],[19]   4,553 [9],[10],[11]          
Cost   608 [3],[6],[19]   608 [3],[6],[19]   4,571 [9],[10],[11]          
Investment, Identifier [Axis]: Smile Brands Group Inc., Health Care Services, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,310 [3],[6],[19]   1,310 [3],[6],[19]   (6) [9],[10],[11]          
Cost   1,340 [3],[6],[19]   1,340 [3],[6],[19]   (12) [9],[10],[11]          
Investment, Identifier [Axis]: Smile Brands Group Inc., Health Care Services, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   3,127   3,127              
Cost [3],[6],[19]   3,199   3,199              
Investment, Identifier [Axis]: Smile Brands Group, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   38   38   655          
Investment, Identifier [Axis]: Sound Point CLO XX, Ltd., Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   1,129   1,129              
Cost [4],[13]   2,201   2,201              
Investment, Identifier [Axis]: Springbrook Software (SBRK Intermediate, Inc.), Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   2,373          
Investment, Identifier [Axis]: Springbrook Software (SBRK Intermediate, Inc.), Enterprise Software & Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   20,695 [3],[6],[22]   20,695 [3],[6],[22]   10,346 [9],[10],[11]          
Cost   20,698 [3],[6],[22]   20,698 [3],[6],[22]   10,179 [9],[10],[11]          
Investment, Identifier [Axis]: Starnmeer B.V., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,453 [3],[6],[7],[13]   2,453 [3],[6],[7],[13]   7,388 [9],[10],[11],[14]          
Cost   2,468 [3],[6],[7],[13]   2,468 [3],[6],[7],[13]   7,391 [9],[10],[11],[14]          
Investment, Identifier [Axis]: Superjet Buyer, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,825   1,825   1,825          
Investment, Identifier [Axis]: Superjet Buyer, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   12,880 [3],[6],[7]   12,880 [3],[6],[7]   22,711 [9],[10],[11]          
Cost   12,841 [3],[6],[7]   12,841 [3],[6],[7]   22,711 [9],[10],[11]          
Investment, Identifier [Axis]: Superjet Buyer, LLC, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (27) [3],[6],[7]   (27) [3],[6],[7]   (37) [9],[10],[11]          
Cost   (32) [3],[6],[7]   (32) [3],[6],[7]   (37) [9],[10],[11]          
Investment, Identifier [Axis]: Syniverse Holdings, Inc., Technology Distributors, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[11]           17,192          
Cost [9],[11]           16,493          
Investment, Identifier [Axis]: Syniverse Holdings, Inc., Technology Distributors, Series A Preferred Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   7,046   7,046              
Cost [6]   7,424   7,424              
Investment, Identifier [Axis]: Syntax Systems Ltd, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,933   1,933   1,933          
Investment, Identifier [Axis]: Syntax Systems Ltd, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   337   337   569          
Investment, Identifier [Axis]: Syntax Systems Ltd, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,912 [3],[6],[13],[22]   1,912 [3],[6],[13],[22]   2,016 [9],[10],[14],[18]          
Cost   1,995 [3],[6],[13],[22]   1,995 [3],[6],[13],[22]   2,018 [9],[10],[14],[18]          
Investment, Identifier [Axis]: Syntax Systems Ltd, Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   646 [3],[6],[13],[22]   646 [3],[6],[13],[22]   432 [9],[10],[14],[18]          
Cost   666 [3],[6],[13],[22]   666 [3],[6],[13],[22]   432 [9],[10],[14],[18]          
Investment, Identifier [Axis]: TA SL Cayman Aggregator Corp., Technology, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   83 [6],[8]   83 [6],[8]   65 [10]          
Cost   50 [6],[8]   50 [6],[8]   50 [10]          
Investment, Identifier [Axis]: TA SL Cayman Aggregator Corp., Technology, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,148 [6]   2,148 [6]   1,960 [10]          
Cost   2,142 [6]   2,142 [6]   1,957 [10]          
Investment, Identifier [Axis]: TPC Group, Inc., Chemicals, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   40,116   40,116              
Cost [3],[6],[35]   40,235   40,235              
Investment, Identifier [Axis]: TPC Group, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   34,322   34,322   0          
Investment, Identifier [Axis]: TSM II Luxco 10 SARL, Chemical & Plastics, Senior Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13]   9,405   9,405              
Cost [3],[6],[13]   10,692   10,692              
Investment, Identifier [Axis]: Tank Holding Corp, Metal & Glass Containers, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   10,919   10,919              
Cost [3],[6],[17]   10,894   10,894              
Investment, Identifier [Axis]: Tank Holding Corp, Metal & Glass Containers, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   (16)   (16)              
Cost [3],[6],[17]   (18)   (18)              
Investment, Identifier [Axis]: Tank Holding Corp, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   873   873   0          
Investment, Identifier [Axis]: Team Car Care, LLC, Automotive, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   12,138   12,138              
Cost [3],[4],[6],[7]   12,298   12,298              
Investment, Identifier [Axis]: Team Services Group, Services: Consumer, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   9,492   9,492              
Cost [3],[4],[6],[7]   9,887   9,887              
Investment, Identifier [Axis]: Team Services Group, Services: Consumer, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[6],[7]   4,900   4,900              
Cost [3],[4],[6],[7]   4,975   4,975              
Investment, Identifier [Axis]: Techone B.V., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,621          
Investment, Identifier [Axis]: Techone B.V., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   205   205   432          
Investment, Identifier [Axis]: Techone B.V., Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,357 [3],[6],[13],[15]   3,357 [3],[6],[13],[15]   8,441 [9],[10],[14],[23]          
Cost   3,784 [3],[6],[13],[15]   3,784 [3],[6],[13],[15]   8,428 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Techone B.V., Technology, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   249 [3],[6],[13],[15]   249 [3],[6],[13],[15]   97 [9],[10],[14],[23]          
Cost   274 [3],[6],[13],[15]   274 [3],[6],[13],[15]   97 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Tencarva Machinery Company, LLC, Capital Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           5,374          
Cost [9],[10],[11]           5,375          
Investment, Identifier [Axis]: Tencarva Machinery Company, LLC, Capital Equipment, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   875   875              
Cost [3],[6],[7]   872   872              
Investment, Identifier [Axis]: Tencarva Machinery Company, LLC, Capital Equipment, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   5,374   5,374              
Cost [3],[6],[7]   5,359   5,359              
Investment, Identifier [Axis]: Tencarva Machinery Company, LLC, Capital Equipment, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (15) [3],[6],[7]   (15) [3],[6],[7]   (20) [9],[10],[11]          
Cost   (17) [3],[6],[7]   (17) [3],[6],[7]   (20) [9],[10],[11]          
Investment, Identifier [Axis]: Tencarva Machinery Company, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   886          
Investment, Identifier [Axis]: Tencarva Machinery Company, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,129   1,129   1,129          
Investment, Identifier [Axis]: Terrybear, Inc., Consumer Products, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   239   239              
Cost [6],[8]   239   239              
Investment, Identifier [Axis]: Terrybear, Inc., Consumer Products, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   254   254              
Cost [6]   253   253              
Investment, Identifier [Axis]: The Caprock Group, Inc. (aka TA/TCG Holdings, LLC), Brokerage, Asset Managers & Exchanges, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   792 [3],[6],[22]   792 [3],[6],[22]   776 [9],[10],[11]          
Cost   781 [3],[6],[22]   781 [3],[6],[22]   776 [9],[10],[11]          
Investment, Identifier [Axis]: The Caprock Group, Inc. (aka TA/TCG Holdings, LLC), Brokerage, Asset Managers & Exchanges, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   (12) [3],[6],[22]   (12) [3],[6],[22]   (14) [9],[10],[11]          
Cost   (13) [3],[6],[22]   (13) [3],[6],[22]   (14) [9],[10],[11]          
Investment, Identifier [Axis]: The Caprock Group, Inc. (aka TA/TCG Holdings, LLC), Brokerage, Asset Managers & Exchanges, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,323 [3],[6],[22]   3,323 [3],[6],[22]   3,267 [10]          
Cost   3,310 [3],[6],[22]   3,310 [3],[6],[22]   3,268 [10]          
Investment, Identifier [Axis]: The Caprock Group, Inc. (aka TA/TCG Holdings, LLC), Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,811   2,811   2,811          
Investment, Identifier [Axis]: The Caprock Group, Inc. (aka TA/TCG Holdings, LLC), Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   827   827   827          
Investment, Identifier [Axis]: The Cleaver-Brooks Company, Inc., Industrial Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[17]   26,294   26,294              
Cost [3],[6],[17]   26,310   26,310              
Investment, Identifier [Axis]: The Cleaver-Brooks Company, Inc., Industrial Equipment, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   5,528   5,528              
Cost [6]   5,533   5,533              
Investment, Identifier [Axis]: The Cleaver-Brooks Company, Inc., Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,583   2,583   0          
Investment, Identifier [Axis]: The Hilb Group, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,204   2,204   2,773          
Investment, Identifier [Axis]: The Hilb Group, LLC, Insurance Brokerage, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   572 [3],[6],[22]   572 [3],[6],[22]   19,874 [9],[10],[11]          
Cost   576 [3],[6],[22]   576 [3],[6],[22]   19,880 [9],[10],[11]          
Investment, Identifier [Axis]: The Hilb Group, LLC, Insurance Brokerage, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,563 [3],[6],[22]   5,563 [3],[6],[22]   (2) [9],[10],[11]          
Cost   5,566 [3],[6],[22]   5,566 [3],[6],[22]   (1) [9],[10],[11]          
Investment, Identifier [Axis]: The Hilb Group, LLC, Insurance Brokerage, First Lien Senior Secured Term Loan 3                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   14,184   14,184              
Cost [3],[6],[22]   14,206   14,206              
Investment, Identifier [Axis]: The Octave Music Group, Inc., Media: Diversified & Production, Partnership Equity                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   971   971              
Cost [6],[8]   677   677              
Investment, Identifier [Axis]: The Octave Music Group, Inc., Media: Diversified & Production, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   12,313   12,313              
Cost [3],[6],[35]   12,283   12,283              
Investment, Identifier [Axis]: Thompson Rivers LLC                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital                 $ 75,000    
Investment, Identifier [Axis]: Thompson Rivers LLC, Investment Funds & Vehicles, 15.90% Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [14]           84,438          
Cost [14]           79,414          
Investment, Identifier [Axis]: Thompson Rivers LLC, Investment Funds & Vehicles, 16.0% Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [13]   43,729   43,729              
Cost [13]   58,604   58,604              
Investment, Identifier [Axis]: Thompson Rivers LLC, Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   43,729   43,729   84,438       10,012  
Investment, Identifier [Axis]: Thompsonn Rivers LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   0          
Total contributed capital   79,411   79,411   79,414          
Investment, Identifier [Axis]: Total Safety U.S. Inc., Diversified Support Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[20]           6,482          
Cost [9],[20]           6,393          
Investment, Identifier [Axis]: Total Safety U.S. Inc., Diversified Support Services, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[19]   6,033   6,033              
Cost [3],[19]   6,162   6,162              
Investment, Identifier [Axis]: Total Safety U.S. Inc., Diversified Support Services, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[19]   3,500   3,500              
Cost [3],[6],[19]   3,500   3,500              
Investment, Identifier [Axis]: Transit Technologies LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   1,857          
Investment, Identifier [Axis]: Transit Technologies LLC, Software, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,800 [3],[6],[7]   5,800 [3],[6],[7]   5,846 [9],[10],[11]          
Cost   5,982 [3],[6],[7]   5,982 [3],[6],[7]   5,946 [9],[10],[11]          
Investment, Identifier [Axis]: Transportation Insight, LLC, Air Freight & Logistics, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,037 [3],[6],[22]   11,037 [3],[6],[22]   11,160 [9],[10],[18]          
Cost   11,186 [3],[6],[22]   11,186 [3],[6],[22]   11,260 [9],[10],[18]          
Investment, Identifier [Axis]: Trident Maritime Systems, Inc., Aerospace & Defense, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   14,583 [3],[6],[7]   14,583 [3],[6],[7]   14,888 [9],[10],[11]          
Cost   14,620 [3],[6],[7]   14,620 [3],[6],[7]   14,665 [9],[10],[11]          
Investment, Identifier [Axis]: Truck-Lite Co., LLC, Automotive Parts & Equipment, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   19,023 [3],[6],[35]   19,023 [3],[6],[35]   14,611 [9],[10],[11]          
Cost   19,064 [3],[6],[35]   19,064 [3],[6],[35]   14,623 [9],[10],[11]          
Investment, Identifier [Axis]: Truck-Lite Co., LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   0   0   4,540          
Investment, Identifier [Axis]: True Religion Apparel, Inc., Retail, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: True Religion Apparel, Inc., Retail, Preferred Unit                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: Trystar, LLC, Power Distribution Solutions, Class A LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   412 [6],[8]   412 [6],[8]   412 [10]          
Cost   481 [6],[8]   481 [6],[8]   481 [10]          
Investment, Identifier [Axis]: Trystar, LLC, Power Distribution Solutions, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   6,830 [3],[6],[7]   6,830 [3],[6],[7]   11,778 [9],[10],[11]          
Cost   6,870 [3],[6],[7]   6,870 [3],[6],[7]   11,777 [9],[10],[11]          
Investment, Identifier [Axis]: Turbo Buyer, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,130   2,130   2,070          
Investment, Identifier [Axis]: Turbo Buyer, Inc., Finance Companies, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,305 [3],[6],[7]   7,305 [3],[6],[7]   8,220 [9],[10],[11]          
Cost   7,420 [3],[6],[7]   7,420 [3],[6],[7]   8,226 [9],[10],[11]          
Investment, Identifier [Axis]: Turf Products, LLC, Landscaping & Irrigation Equipment Distributor, Senior Subordinated Debt                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   8,584 [6],[42]   8,584 [6],[42]   8,627 [10],[36]          
Cost   8,384 [6],[42]   8,384 [6],[42]   8,384 [10],[36]          
Investment, Identifier [Axis]: Turnberry Solutions, Inc., Consumer Cyclical, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,907 [3],[6],[12]   4,907 [3],[6],[12]   4,423 [9],[10],[11]          
Cost   4,908 [3],[6],[12]   4,908 [3],[6],[12]   4,406 [9],[10],[11]          
Investment, Identifier [Axis]: U.S. Gas & Electric, Inc., Energy Services, Second Lien Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,814 [6],[42]   1,814 [6],[42]   1,785 [10],[36]          
Cost   1,785 [6],[42]   1,785 [6],[42]   1,785 [10],[36]          
Investment, Identifier [Axis]: U.S. Gas & Electric, Inc., Energy Services, Second Lien Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   0 [6],[42],[50]   0 [6],[42],[50]   0 [10],[36],[51]          
Cost   0 [6],[42],[50]   0 [6],[42],[50]   0 [10],[36],[51]          
Investment, Identifier [Axis]: U.S. Silica Company, Metal & Glass Containers, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,400 [3],[13],[22]   1,400 [3],[13],[22]   1,437 [9],[14],[18]          
Cost   1,462 [3],[13],[22]   1,462 [3],[13],[22]   1,474 [9],[14],[18]          
Investment, Identifier [Axis]: UKFast Leaders Limited, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   9,726 [3],[6],[13],[28]   9,726 [3],[6],[13],[28]   12,090 [9],[10],[14],[27]          
Cost   11,431 [3],[6],[13],[28]   11,431 [3],[6],[13],[28]   11,399 [9],[10],[14],[27]          
Investment, Identifier [Axis]: USLS Acquisition, Inc. (f/k/a US Legal Support, Inc.), Legal Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           16,222          
Cost [9],[10],[11]           16,065          
Investment, Identifier [Axis]: USLS Acquisition, Inc. (f/k/a US Legal Support, Inc.), Legal Services, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   15,791   15,791              
Cost [3],[6],[35]   15,938   15,938              
Investment, Identifier [Axis]: USLS Acquisition, Inc. (f/k/a US Legal Support, Inc.), Legal Services, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[35]   128   128              
Cost [3],[6],[35]   129   129              
Investment, Identifier [Axis]: USLS Acquisition, Inc.(f/k/a US Legal Support, Inc.), Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   3,629   3,629   0          
Investment, Identifier [Axis]: Union Bidco Limited, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   89   89   0          
Investment, Identifier [Axis]: Union Bidco Limited, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[28]   784   784              
Cost [3],[6],[13],[28]   852   852              
Investment, Identifier [Axis]: United Therapy Holding III GmbH, Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,488   1,488   0          
Investment, Identifier [Axis]: United Therapy Holding III GmbH, Healthcare, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[21]   665   665              
Cost [3],[6],[13],[21]   731   731              
Investment, Identifier [Axis]: Utac Ceram, Business Services, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,451 [3],[6],[13],[15]   1,451 [3],[6],[13],[15]   1,673 [9],[10],[14],[23]          
Cost   1,710 [3],[6],[13],[15]   1,710 [3],[6],[13],[15]   1,706 [9],[10],[14],[23]          
Investment, Identifier [Axis]: Utac Ceram, Business Services, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   3,475 [3],[6],[7],[13]   3,475 [3],[6],[7],[13]   3,451 [9],[10],[11],[14]          
Cost   3,463 [3],[6],[7],[13]   3,463 [3],[6],[7],[13]   3,456 [9],[10],[11],[14]          
Investment, Identifier [Axis]: VOYA CLO 2015-2, LTD., Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   91   91              
Cost [4],[13]   2,930   2,930              
Investment, Identifier [Axis]: VOYA CLO 2016-2, LTD., Multi-Sector Holdings, Subordinated Structured Notes                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[13]   2,212   2,212              
Cost [4],[13]   3,310   3,310              
Investment, Identifier [Axis]: Validity, Inc., IT Consulting & Other Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,754 [3],[6],[22]   4,754 [3],[6],[22]   4,764 [9],[10],[18]          
Cost   4,706 [3],[6],[22]   4,706 [3],[6],[22]   4,687 [9],[10],[18]          
Investment, Identifier [Axis]: Velocity Pooling Vehicle, LLC, Automotive, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   2   2              
Cost [4],[6],[8]   60   60              
Investment, Identifier [Axis]: Velocity Pooling Vehicle, LLC, Automotive, Warrants                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   3   3              
Cost [4],[6],[8]   72   72              
Investment, Identifier [Axis]: Victoria Bidco Limited, Industrial Machinery, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[38]   3,396   3,396              
Cost [3],[6],[13],[38]   4,048   4,048              
Investment, Identifier [Axis]: Vision Solutions Inc., Business Equipment & Services, Second Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[22]   5,383   5,383              
Cost [3],[4],[22]   6,497   6,497              
Investment, Identifier [Axis]: VistaJet Pass Through Trust 2021-1B, Airlines, Structured Secured Note - Class B                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   4,274 [6]   4,274 [6]   4,905          
Cost   4,643 [6]   4,643 [6]   5,000          
Investment, Identifier [Axis]: Vital Buyer, LLC, Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   7,723 [3],[6],[7]   7,723 [3],[6],[7]   7,676 [9],[10],[11]          
Cost   7,593 [3],[6],[7]   7,593 [3],[6],[7]   7,656 [9],[10],[11]          
Investment, Identifier [Axis]: Vital Buyer, LLC, Technology, Partnership Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   329 [6],[8]   329 [6],[8]   171 [10]          
Cost   164 [6],[8]   164 [6],[8]   164 [10]          
Investment, Identifier [Axis]: W2O Holdings, Inc., Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,622   2,622   3,832          
Investment, Identifier [Axis]: W2O Holdings, Inc., Healthcare Technology, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [9],[10],[11]           2,152          
Cost [9],[10],[11]           2,090          
Investment, Identifier [Axis]: W2O Holdings, Inc., Healthcare Technology, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   (16)   (16)              
Cost [3],[6],[7]   (36)   (36)              
Investment, Identifier [Axis]: W2O Holdings, Inc., Healthcare Technology, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[19]   3,323   3,323              
Cost [6],[19]   3,343   3,343              
Investment, Identifier [Axis]: Waccamaw River LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,480   2,480   11,280          
Fair value of investment owned           13,501       $ 0  
Total contributed capital   27,800   27,800   19,000     $ 25,000    
Total return of capital (recallable)   5,280   5,280   5,280          
Investment, Identifier [Axis]: Waccamaw River LLC Capital Commitment - Funded                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital   22,500   22,500              
Investment, Identifier [Axis]: Waccamaw River LLC, Investment Funds & Vehicles                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [14]           13,501          
Cost [14]           13,720          
Investment, Identifier [Axis]: Waccamaw River LLC, Investment Funds & Vehicles, 20% Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [13]   21,371   21,371              
Cost [13]   22,520   22,520              
Investment, Identifier [Axis]: Waccamaw River LLC, Member Interest                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   21,371   21,371   13,501          
Investment, Identifier [Axis]: Waccamaw River, Joint Venture                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,480   2,480   11,280          
Investment, Identifier [Axis]: Walker Edison Furniture Company LLC, Consumer Goods: Durable, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   220   220              
Cost [4],[6],[8]   3,598   3,598              
Investment, Identifier [Axis]: Watermill-QMC Midco, Inc., Automotive, Equity (1.62% Partnership Interest)                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[6],[8]   0   0              
Cost [4],[6],[8]   0   0              
Investment, Identifier [Axis]: Wawona Delaware Holdings, LLC, Beverage & Food, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [4],[7]   34   34              
Cost [4],[7]   41   41              
Investment, Identifier [Axis]: Wheels Up Experience Inc, Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6]   14,606   14,606              
Cost [6]   14,400   14,400              
Investment, Identifier [Axis]: Wok Holdings Inc., Retail, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[4],[7]   42   42              
Cost [3],[4],[7]   48   48              
Investment, Identifier [Axis]: Woodland Foods, Inc., Line of Credit                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   792   792   2,070          
Investment, Identifier [Axis]: Woodland Foods, LLC, Food & Beverage, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,449 [6],[8]   1,449 [6],[8]   1,663 [10]          
Cost   1,663 [6],[8]   1,663 [6],[8]   1,663 [10]          
Investment, Identifier [Axis]: Woodland Foods, LLC, Food & Beverage, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   5,254 [3],[6],[7]   5,254 [3],[6],[7]   11,282 [9],[10],[11]          
Cost   5,359 [3],[6],[7]   5,359 [3],[6],[7]   11,285 [9],[10],[11]          
Investment, Identifier [Axis]: Woodland Foods, LLC, Food & Beverage, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,367 [3],[6],[7]   1,367 [3],[6],[7]   127 [9],[10],[11]          
Cost   1,411 [3],[6],[7]   1,411 [3],[6],[7]   128 [9],[10],[11]          
Investment, Identifier [Axis]: World 50, Inc., Professional Services, First Lien Senior Secured Term Loan 1                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   8,828 [3],[6],[22]   8,828 [3],[6],[22]   3,280 [9],[10],[18]          
Cost   8,808 [3],[6],[22]   8,808 [3],[6],[22]   3,202 [9],[10],[18]          
Investment, Identifier [Axis]: World 50, Inc., Professional Services, First Lien Senior Secured Term Loan 2                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   2,435 [3],[6],[22]   2,435 [3],[6],[22]   8,872 [9],[10],[18]          
Cost   2,426 [3],[6],[22]   2,426 [3],[6],[22]   8,852 [9],[10],[18]          
Investment, Identifier [Axis]: Xeinadin Bidco Limited, CAF Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,886   2,886   0          
Investment, Identifier [Axis]: Xeinadin Bidco Limited, Financial Other, Common Stock                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8],[13]   510   510              
Cost [6],[8],[13]   565   565              
Investment, Identifier [Axis]: Xeinadin Bidco Limited, Financial Other, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[28]   5,035   5,035              
Cost [3],[6],[13],[28]   5,569   5,569              
Investment, Identifier [Axis]: Xeinadin Bidco Limited, Financial Other, Subordinated Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[13]   2,316   2,316              
Cost [6],[13]   2,549   2,549              
Investment, Identifier [Axis]: ZB Holdco LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,352   1,352   0          
Investment, Identifier [Axis]: ZB Holdco LLC, Food & Beverage, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   2,634   2,634              
Cost [3],[6],[7]   2,631   2,631              
Investment, Identifier [Axis]: ZB Holdco LLC, Food & Beverage, LLC Units                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [6],[8]   179   179              
Cost [6],[8]   153   153              
Investment, Identifier [Axis]: ZB Holdco LLC, Food & Beverage, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[7]   (13)   (13)              
Cost [3],[6],[7]   (15)   (15)              
Investment, Identifier [Axis]: ZB Holdco LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   845   845   0          
Investment, Identifier [Axis]: Zeppelin Bidco Limited, Capex / Acquisition Facility                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   2,335   2,335   0          
Investment, Identifier [Axis]: Zeppelin Bidco Limited, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   491   491   0          
Investment, Identifier [Axis]: Zeppelin Bidco Limited, Services: Business, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[28]   5,229   5,229              
Cost [3],[6],[13],[28]   6,137   6,137              
Investment, Identifier [Axis]: Zeppelin Bidco Limited, Services: Business, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[13],[28]   (11)   (11)              
Cost [3],[6],[13],[28]   (1)   (1)              
Investment, Identifier [Axis]: eShipping, LLC, Delayed Draw Term Loan                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,650   1,650   2,548          
Investment, Identifier [Axis]: eShipping, LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   1,486   1,486   1,232          
Investment, Identifier [Axis]: eShipping, LLC, Transportation Services, First Lien Senior Secured Term Loan                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   3,520   3,520              
Cost [3],[6],[22]   3,440   3,440              
Investment, Identifier [Axis]: eShipping, LLC, Transportation Services, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned [3],[6],[22]   (3)   (3)              
Cost [3],[6],[22]   $ (25)   (25)              
Sierra Acquisition                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments       $ 442,200              
Number of portfolio companies | investment   5   5              
MVC Acquisition                      
Summary of Investment Holdings [Line Items]                      
Number of portfolio companies | investment   2   2              
Fair Value, Inputs, Level 3                      
Summary of Investment Holdings [Line Items]                      
Unrealized gain (loss)       $ (44,300) $ 3,100            
Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Repayments received/sales of portfolio investments       875,900   698,500          
Gain (loss) on sale of investments   $ (5,400) $ (1,100) (5,600) 300            
Due from related parties   46,000   $ 46,000   $ 216,900          
Percentage of Total Portfolio | Portfolio Company Investment Risk | Single Portfolio Company                      
Summary of Investment Holdings [Line Items]                      
Concentration risk, percent       5.90%   5.50%          
Line of Credit                      
Summary of Investment Holdings [Line Items]                      
Long-term debt, gross   650,989   $ 650,989   $ 655,189          
Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing             $ 50,000       $ 50,000
Fair value of investment owned   1,213,233   1,213,233   1,245,647          
Thompson Rivers LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,152,010   1,152,010   3,063,035          
Cost   1,231,727   1,231,727   $ 3,024,529          
Total dividend income   2,200   7,700              
Distributions of realized gains by investment companies   $ 12,000                  
Distributions of realized gains by investment companies       $ 20,800              
Investment owned, outstanding loans | loan   6,913   6,913   15,617          
Investment owned, average unpaid balance   $ 200   $ 200   $ 200          
Investment owned, weighted average coupon rate   4.00%   4.00%   4.00%          
Thompson Rivers LLC | JPMorgan Chase Bank                      
Summary of Investment Holdings [Line Items]                      
Repurchase agreement counterparty, amount at risk   $ 284,800   $ 284,800   $ 694,800          
Thompson Rivers LLC | Bank of America N.A.,                      
Summary of Investment Holdings [Line Items]                      
Repurchase agreement counterparty, amount at risk   546,300   546,300   1,245,200          
Thompson Rivers LLC | Barclays Bank                      
Summary of Investment Holdings [Line Items]                      
Repurchase agreement counterparty, amount at risk   241,500   241,500   $ 933,100          
Waccamaw River, LLC                      
Summary of Investment Holdings [Line Items]                      
Total dividend income   $ 500   $ 1,300              
Investment owned, outstanding loans | investment   15,017,000   15,017,000   5,500          
Investment company, remaining average life to maturity       44 months 17 days   46 months 15 days          
Average loan amount   $ 11,649   $ 11,649   $ 11,280          
Investment company, weighted average interest rate       11.60%   10.90%          
Sierra JV                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   115,670   $ 115,670              
Cost   129,684   129,684              
Total dividend income   1,600   3,200              
Distributions of realized gains by investment companies   $ 9,000   $ 35,700              
Weighted average yield   7.00%   7.00%              
SCRS | Investment, Identifier [Axis]: Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing                     $ 500,000
Jocassee Partners LLC | Bank Of America Subscription Facility | Subscription Facility | Line of Credit                      
Summary of Investment Holdings [Line Items]                      
Borrowings under credit facilities   $ 168,200   $ 168,200   $ 176,300          
Jocassee Partners LLC | Citibank N.A. Subscription Facility | Subscription Facility | Line of Credit                      
Summary of Investment Holdings [Line Items]                      
Borrowings under credit facilities   353,500   353,500   342,800          
Jocassee Partners LLC | Term Debt Securitization | Subscription Facility | Line of Credit                      
Summary of Investment Holdings [Line Items]                      
Borrowings under credit facilities   323,200   323,200   323,100          
All Members Of Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital   450,000   450,000              
All Members Of Jocassee Partners LLC | Investment, Identifier [Axis]: Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   215,000   215,000   220,000          
Total contributed capital   385,000   385,000   330,000          
Thompson Rivers LLC                      
Summary of Investment Holdings [Line Items]                      
Dividends   89,100   178,500              
All Member Of Waccamaw River LLC                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital   125,000   125,000              
All Member Of Waccamaw River LLC | Investment, Identifier [Axis]: Waccamaw River LLC                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   12,400   12,400   56,400          
Total contributed capital   126,620   126,620   82,620          
Total return of capital (recallable)   14,020   14,020   14,020          
All Member Of Waccamaw River LLC | Investment, Identifier [Axis]: Waccamaw River LLC | Affiliated Entity                      
Summary of Investment Holdings [Line Items]                      
Total unused commitments to extend financing   7,400   7,400   33,800          
Total return of capital (recallable)   7,000   7,000              
All Member Of Waccamaw River LLC | Investment, Identifier [Axis]: Waccamaw River LLC Capital Commitment - Funded                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital           112,600          
Waccamaw River, LLC                      
Summary of Investment Holdings [Line Items]                      
Dividends   2,700   6,600              
Waccamaw River, LLC | JPMorgan Chase Bank N.A. Non-Recourse Loan | Secured Debt                      
Summary of Investment Holdings [Line Items]                      
Long-term debt, gross   56,700   56,700              
Waccamaw River, LLC | Barclay Bank PLC Non-Recourse Loan | Secured Debt                      
Summary of Investment Holdings [Line Items]                      
Long-term debt, gross   24,100   24,100              
All Members Of Sierra JV                      
Summary of Investment Holdings [Line Items]                      
Number of members | member 4                    
All Members Of Sierra JV | Investment, Identifier [Axis]: Sierra Senior Loan Strategy JV LLC (Sierra JV)                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital   124,500   124,500              
MMALIC                      
Summary of Investment Holdings [Line Items]                      
Number of members | member 2                    
MMALIC | Investment, Identifier [Axis]: Sierra Senior Loan Strategy JV LLC (Sierra JV)                      
Summary of Investment Holdings [Line Items]                      
Total contributed capital   14,500   14,500              
Sierra JV                      
Summary of Investment Holdings [Line Items]                      
Dividends   12,000   43,800              
Sierra JV | Revolving Credit Facility | Line of Credit                      
Summary of Investment Holdings [Line Items]                      
Borrowings under credit facilities   75,000   75,000              
Existing Portfolio                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments   50,700 60,300 221,700 156,300            
Investment in joint ventures                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments     3,800 13,800 9,300            
Investment in joint ventures | Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   80,201   80,201   127,092          
Cost   92,061   92,061   111,490          
Equity Co-Investments                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments     $ 89,800   89,800            
Joint Venture Equity Portfolio Companies                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments         30,000            
Long-Term Investment                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments       938,653 816,807            
Repayments received/sales of portfolio investments       900,343 648,320            
Long-Term Investment | Jocassee Partners LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,219,093   1,219,093   1,258,219          
Cost   1,318,190   $ 1,318,190   $ 1,242,219          
Long-Term Investment | Jocasse Portfolio                      
Summary of Investment Holdings [Line Items]                      
Interest-earning assets, average yield       7.40%   5.30%          
Ginnie Mae Early Buyout Loans | Thompson Rivers LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   1,200,000   $ 1,200,000   $ 3,100,000          
Consumer Loan | Waccamaw River, LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   169,100   169,100   60,800          
Cash and Cash Equivalents | Thompson Rivers LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   203,500   203,500   220,600          
Cash and Cash Equivalents | Waccamaw River, LLC                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   11,500   11,500   4,900          
Unfunded Securities | Investment, Identifier [Axis]: Eclipse Business Capital Holdings LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned               13,600      
Funded Securities | Investment, Identifier [Axis]: Eclipse Business Capital Holdings LLC, Revolver                      
Summary of Investment Holdings [Line Items]                      
Fair value of investment owned   $ 6,200   6,200   $ 1,800          
Revolving Line Of Credit | Minimum | Eclipse Business Capital Holdings LLC                      
Summary of Investment Holdings [Line Items]                      
Investment owned, face amount               10,000      
Revolving Line Of Credit | Maximum | Eclipse Business Capital Holdings LLC                      
Summary of Investment Holdings [Line Items]                      
Investment owned, face amount               $ 125,000      
Investments With No Previous Contractual Commitment To Provide Financing                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments       1,301,900              
Investment With Previous Commitment To Provide FInancing                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments       $ 71,000              
Investment, Excluding Short Term Investment, With No Previous Commitment To Provide Financing                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments         757,800            
Investment, Excluding Short Term Investment, With Previous Commitment To Provide Financing                      
Summary of Investment Holdings [Line Items]                      
Purchases of portfolio investments         $ 57,500            
Investment Denominated In Canadian Dollars                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   1   1   1          
Investment Denominated In Danish Kroner                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   1   1   1          
Investment Denominated In Australian Dollars                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   10   10   5          
Investment Denominated In New Zealand Dollars                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   2   2              
Investment Denominated In Norwegian Krone                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   1   1              
Investment Denominated In Swiss Francs                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   1   1              
Investment Denominated In Swedish Krone                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   1   1   1          
Investment Denominated In Euros                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   54   54   36          
Investment Denominated In British Pounds Sterling                      
Summary of Investment Holdings [Line Items]                      
Number of investments | investment   25   25   18          
[1] Some or all of the investment is or will be encumbered as security for the Company's $1.1 billion senior secured credit facility with ING Capital LLC initially entered into in February 2019 (as amended, restated and otherwise modified from time to time, the "February 2019 Credit Facility").
[2] Some or all of the investment is or will be encumbered as security for the Company's senior secured credit facility with ING Capital LLC.
[3] Debt investment includes interest rate floor feature.
[4] Investment was purchased as part of the Sierra Acquisition and is part of the Sierra Reference Portfolio for purposes of the Sierra Credit Support Agreement.
[5] Non-accrual investment.
[6] The fair value of the investment was determined using significant unobservable inputs.
[7] The interest rate on these loans is subject to 3 Month LIBOR, which as of September 30, 2022 was 3.75471%.
[8] Investment is non-income producing.
[9] Debt investment includes interest rate floor feature.
[10] The fair value of the investment was determined using significant unobservable inputs.
[11] The interest rate on these loans is subject to 3 Month LIBOR, which as of December 31, 2021 was 0.20913%.
[12] The interest rate on these loans is subject to 6 Month SOFR, which as of September 30, 2022 was 3.99102%.
[13] Investment is not a qualifying investment as defined under Section 55(a) of the 1940 Act. Non-qualifying assets represent 26.0% of total investments at fair value as of September 30, 2022. Qualifying assets must represent at least 70% of total assets at the time of acquisition of any additional non-qualifying assets. If at any time qualifying assets do not represent at least 70% of the Company's total assets, the Company will be precluded from acquiring any additional non-qualifying asset until such time as it complies with the requirements of Section 55(a).
[14] Investment is not a qualifying investment as defined under Section 55(a) of the 1940 Act. Non-qualifying assets represent 25.7% of total investments at fair value as of December 31, 2021. Qualifying assets must represent at least 70% of total assets at the time of acquisition of any additional non-qualifying assets. If at any time qualifying assets do not represent at least 70% of the Company's total assets, the Company will be precluded from acquiring any additional non-qualifying asset until such time as it complies with the requirements of Section 55(a).
[15] The interest rate on these loans is subject to 3 Month EURIBOR, which as of September 30, 2022 was 1.17300%.
[16] The interest rate on these loans is subject to 1 Month BBSY, which as of September 30, 2022 was 2.70750%.
[17] The interest rate on these loans is subject to 1 Month SOFR, which as of September 30, 2022 was 3.04205%.
[18] The interest rate on these loans is subject to 1 Month LIBOR, which as of December 31, 2021 was 0.10125%.
[19] The interest rate on these loans is subject to 6 Month LIBOR, which as of September 30, 2022 was 4.23200%.
[20] The interest rate on these loans is subject to 6 Month LIBOR, which as of December 31, 2021 was 0.33875%.
[21] The interest rate on these loans is subject to 6 Month EURIBOR, which as of September 30, 2022 was 1.80900%.
[22] The interest rate on these loans is subject to 1 Month LIBOR, which as of September 30, 2022 was 3.14271%.
[23] The interest rate on these loans is subject to 3 Month EURIBOR, which as of December 31, 2021 was -0.57200%.
[24] The interest rate on these loans is subject to 3 Month GBP LIBOR, which as of December 31, 2021 was 0.26225%.
[25] The interest rate on these loans is subject to 6 Month SONIA, which as of September 30, 2022 was 4.12810%.
[26] The interest rate on these loans is subject to 6 Month SONIA, which as of December 31, 2021 was 0.49870%.
[27] The interest rate on these loans is subject to 3 Month SONIA, which as of December 31, 2021 was 0.33830%.
[28] The interest rate on these loans is subject to 3 Month SONIA, which as of September 30, 2022 was 3.22510%.
[29] The interest rate on these loans is subject to 6 Month EURIBOR, which as of December 31, 2021 was -0.54600%.
[30] The interest rate on these loans is subject to 6 Month BBSY, which as of September 30, 2022 was 3.56880%.
[31] The interest rate on these loans is subject to 3 Month BBSY, which as of December 31, 2021 was 0.06770%.
[32] The interest rate on these loans is subject to 3 Month STIBOR, which as of September 30, 2022 was 1.72500%.
[33] The interest rate on these loans is subject to 3 Month STIBOR, which as of December 31, 2021 was -0.00050%.
[34] The interest rate on these loans is subject to 6 Month GBP LIBOR, which as of December 31, 2021 was 0.47363%.
[35] The interest rate on these loans is subject to 3 Month SOFR, which as of September 30, 2022 was 3.59329%.
[36] Investment was purchased as part of the MVC Acquisition and is part of the MVC Reference Portfolio for purposes of the MVC Credit Support Agreement.
[37] The interest rate on these loans is subject to Prime, which as of September 30, 2022 was 6.25000%.
[38] The interest rate on these loans is subject to 1 Month SONIA, which as of September 30, 2022 was 2.25330%.
[39] The interest rate on these loans is subject to 3 Month SOFR, which as of December 31, 2021 was 0.09125%.
[40] The interest rate on these loans is subject to 3 Month CDOR, which as of September 30, 2022 was 4.20000%.
[41] The interest rate on these loans is subject to 3 Month CDOR, which as of December 31, 2021 was 0.51750%.
[42] Investment was purchased as part of the MVC Acquisition and is part of the MVC Reference Portfolio for purposes of the MVC Credit Support Agreement.
[43] Non-accrual investment.
[44] The interest rate on these loans is subject to 3 Month BBSY, which as of September 30, 2022 was 3.06310%.
[45] The interest rate on these loans is subject to 1 Month EURIBOR, which as of September 30, 2022 was 0.67900%.
[46] The interest rate on these loans is subject to 3 Month BKBM, which as of September 30, 2022 was 3.64000%.
[47] The interest rate on these loans is subject to 1 Month NIBOR, which as of September 30, 2022 was 2.70000%.
[48] The interest rate on these loans is subject to 1 Month BBSY, which as of December 31, 2021 was 0.01500%.
[49] The interest rate on these loans is subject to 3 Month SARON, which as of September 30, 2022 was 0.43653%.
[50] In 2017, MVC received $5.7 million of 9.5% second lien callable notes due in 2025, in lieu of an escrow to satisfy any indemnification claims associated with MVC’s sale of its equity investment in U.S. Gas & Electric ("U.S. Gas"). Effective January 1, 2018, the cost basis of the U.S. Gas second lien loan was decreased by approximately $3.0 million due to a working capital adjustment. This loan is still subject to indemnification adjustments.
[51] In 2017, MVC received $5.7 million of 9.5% second lien callable notes due in 2025, in lieu of an escrow to satisfy any indemnification claims associated with MVC’s sale of its equity investment in U.S. Gas. Effective January 1, 2018, the cost basis of the U.S. Gas second lien loan was decreased by approximately $3.0 million due to a working capital adjustment. This loan is still subject to indemnification adjustments.