v3.25.3
Fair Value Measurement - Summary of Assets and Liabilities Categorized Within Fair Value Hierarchy (Details) - USD ($)
$ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2025
Dec. 31, 2024
Assets    
Debt investments, Fair Value $ 3,196,933 $ 3,475,258
Debt investments, Fair Value 3,229,626 3,500,496
Debt investments, Fair Value 3,229,759 3,500,496
Open Forward Foreign Currency Contract, Identifier [Axis]: Foreign Currency Forward Contracts    
Assets    
Unrealized appreciation (depreciation) (245) (38)
Liabilities    
Unrealized Appreciation (Depreciation) (245) (38)
Open Forward Foreign Currency Contract, Identifier [Axis]: Foreign Currency Forward Contracts Level 1    
Assets    
Unrealized appreciation (depreciation) 0 0
Liabilities    
Unrealized Appreciation (Depreciation) 0 0
Open Forward Foreign Currency Contract, Identifier [Axis]: Foreign Currency Forward Contracts Level 2    
Assets    
Unrealized appreciation (depreciation) (245) (38)
Liabilities    
Unrealized Appreciation (Depreciation) (245) (38)
Open Forward Foreign Currency Contract, Identifier [Axis]: Foreign Currency Forward Contracts Level 3    
Assets    
Unrealized appreciation (depreciation) 0 0
Liabilities    
Unrealized Appreciation (Depreciation) 0 0
Open Forward Foreign Currency Contract, Identifier [Axis]: Interest Rate Swaps    
Assets    
Unrealized appreciation (depreciation) (2,794) (0)
Liabilities    
Unrealized Appreciation (Depreciation) (2,794) (0)
Open Forward Foreign Currency Contract, Identifier [Axis]: Interest Rate Swaps Level 1    
Assets    
Unrealized appreciation (depreciation) 0 0
Liabilities    
Unrealized Appreciation (Depreciation) 0 0
Open Forward Foreign Currency Contract, Identifier [Axis]: Interest Rate Swaps Level 2    
Assets    
Unrealized appreciation (depreciation) (2,794) (0)
Liabilities    
Unrealized Appreciation (Depreciation) (2,794) (0)
Open Forward Foreign Currency Contract, Identifier [Axis]: Interest Rate Swaps Level 3    
Assets    
Unrealized appreciation (depreciation) 0 0
Liabilities    
Unrealized Appreciation (Depreciation) 0 0
Open Forward Foreign Currency Contract, Identifier [Axis]: Total Liabilities    
Assets    
Unrealized appreciation (depreciation) (3,039) (38)
Liabilities    
Unrealized Appreciation (Depreciation) (3,039) (38)
Open Forward Foreign Currency Contract, Identifier [Axis]: Total Liabilities Level 1    
Assets    
Unrealized appreciation (depreciation) (0) (0)
Liabilities    
Unrealized Appreciation (Depreciation) (0) (0)
Open Forward Foreign Currency Contract, Identifier [Axis]: Total Liabilities Level 2    
Assets    
Unrealized appreciation (depreciation) (3,039) (38)
Liabilities    
Unrealized Appreciation (Depreciation) (3,039) (38)
Open Forward Foreign Currency Contract, Identifier [Axis]: Total Liabilities Level 3    
Assets    
Unrealized appreciation (depreciation) (0) (0)
Liabilities    
Unrealized Appreciation (Depreciation) (0) (0)
1st Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 2,998,388 3,179,820
1st Lien/Last-Out Unitranche    
Assets    
Debt investments, Fair Value 93,805 165,905
2nd Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 47,963 46,786
Unsecured Debt    
Assets    
Debt investments, Fair Value 8,391 16,790
Preferred Stock    
Assets    
Equity, Fair Value 26,147 31,246
Common Stock    
Assets    
Equity, Fair Value 22,028 34,290
Warrants    
Assets    
Warrants, Fair Value 211 421
Affiliated Money Market Fund    
Assets    
Debt investments, Fair Value 32,693 25,238
Interest Rate Swaps    
Assets    
Unrealized appreciation (depreciation) 133 0
Liabilities    
Unrealized Appreciation (Depreciation) 133 0
Level 1    
Assets    
Debt investments, Fair Value 32,757 25,362
Level 1 | 1st Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 0 0
Level 1 | 1st Lien/Last-Out Unitranche    
Assets    
Debt investments, Fair Value 0 0
Level 1 | 2nd Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 0 0
Level 1 | Unsecured Debt    
Assets    
Debt investments, Fair Value 0 0
Level 1 | Preferred Stock    
Assets    
Equity, Fair Value 0 0
Level 1 | Common Stock    
Assets    
Equity, Fair Value 64 124
Level 1 | Warrants    
Assets    
Warrants, Fair Value 0 0
Level 1 | Affiliated Money Market Fund    
Assets    
Debt investments, Fair Value 32,693 25,238
Level 1 | Interest Rate Swaps    
Assets    
Unrealized appreciation (depreciation) 0 0
Liabilities    
Unrealized Appreciation (Depreciation) 0 0
Level 2    
Assets    
Debt investments, Fair Value 23,468 43,137
Level 2 | 1st Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 23,335 43,137
Level 2 | 1st Lien/Last-Out Unitranche    
Assets    
Debt investments, Fair Value 0 0
Level 2 | 2nd Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 0 0
Level 2 | Unsecured Debt    
Assets    
Debt investments, Fair Value 0 0
Level 2 | Preferred Stock    
Assets    
Equity, Fair Value 0 0
Level 2 | Common Stock    
Assets    
Equity, Fair Value 0 0
Level 2 | Warrants    
Assets    
Warrants, Fair Value 0 0
Level 2 | Affiliated Money Market Fund    
Assets    
Debt investments, Fair Value 0 0
Level 2 | Interest Rate Swaps    
Assets    
Unrealized appreciation (depreciation) 133 0
Liabilities    
Unrealized Appreciation (Depreciation) 133 0
Level 3    
Assets    
Debt investments, Fair Value 3,173,534 3,431,997
Level 3 | 1st Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 2,975,053 3,136,683
Level 3 | 1st Lien/Last-Out Unitranche    
Assets    
Debt investments, Fair Value 93,805 165,905
Level 3 | 2nd Lien/Senior Secured Debt    
Assets    
Debt investments, Fair Value 47,963 46,786
Level 3 | Unsecured Debt    
Assets    
Debt investments, Fair Value 8,391 16,790
Level 3 | Preferred Stock    
Assets    
Equity, Fair Value 26,147 31,246
Level 3 | Common Stock    
Assets    
Equity, Fair Value 21,964 34,166
Level 3 | Warrants    
Assets    
Warrants, Fair Value 211 421
Level 3 | Affiliated Money Market Fund    
Assets    
Debt investments, Fair Value 0 0
Level 3 | Interest Rate Swaps    
Assets    
Unrealized appreciation (depreciation) 0 0
Liabilities    
Unrealized Appreciation (Depreciation) $ 0 $ 0