Fair Value of Financial Instruments - Fair Value of Level 3 Investments at Fair Value Significant Unobservable Inputs Used in Valuations (Parenthetical) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
First-lien Debt Investments
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Debt investments	$ 2,850,885	$ 800,995
First-lien Debt Investments | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Debt investments	2,848,805	$ 800,995
Asset Valuation Waterfall | First-lien Debt Investments | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Debt investments	77,900
Black Scholes Model | Equity and Other Investments | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Equity investment	4,600
Cost Model | Equity and Other Investments | Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Equity investment	$ 19,200