v3.25.0.1
Borrowings - GBDC 3 2022 Debt Securitization (Narrative) (Details)
$ in Thousands
3 Months Ended 4 Months Ended
Jun. 03, 2024
USD ($)
Dec. 31, 2024
USD ($)
portfolioCompany
Sep. 30, 2024
USD ($)
portfolioCompany
Debt Instrument [Line Items]      
Investments, at fair value   $ 8,685,231 [1] $ 8,235,411 [2]
GBDC 3 2022 Debt Securitization      
Debt Instrument [Line Items]      
Debt instrument, face amount $ 401,750    
Debt instrument, basis spread on variable rate   4.60%  
Repayments of debt     $ 14,751
Number of investment portfolio company | portfolioCompany   52 55
Investments, at fair value   $ 346,859 $ 377,755
GBDC 3 2022 Debt Securitization | Subordinated debt      
Debt Instrument [Line Items]      
Debt instrument, face amount 149,750    
GBDC 3 2022 Debt Securitization | Class A Senior Secured Floating Rate Notes      
Debt Instrument [Line Items]      
Debt instrument, face amount $ 252,000    
Debt instrument, basis spread on variable rate 2.00%    
[1] The fair values of investments were valued using significant unobservable inputs, unless noted otherwise. See “Note 6. Fair Value Measurements”.
[2] The fair values of investments were valued using significant unobservable inputs, unless noted otherwise. See “Note 6. Fair Value Measurements”.