v3.26.3
Fair Value Measurement - Summary of Significant Unobservable Inputs of the Company's Level 3 Financial Instruments (Detail) - Fair Value, Inputs, Level 3 [Member] - USD ($)
$ in Thousands
 9 Months Ended 12 Months Ended
Sep. 30, 2026
Dec. 31, 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 4,682,692 $ 2,958,691
Subordinated Notes [Member] | Annual Prepayment Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input   Annual Prepayment Rate
Range   20.00
Subordinated Notes [Member] | Annual Prepayment Rate [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   20.00
Subordinated Notes [Member] | Reinvestment Spread [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input   Reinvestment Spread
Subordinated Notes [Member] | Reinvestment Spread [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   3.20
Subordinated Notes [Member] | Reinvestment Spread [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   5.05
Subordinated Notes [Member] | Reinvestment Spread [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   4.18
Subordinated Notes [Member] | Reinvestment Price [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input   Reinvestment Price
Subordinated Notes [Member] | Reinvestment Price [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   99.00
Subordinated Notes [Member] | Reinvestment Price [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   99.50
Subordinated Notes [Member] | Reinvestment Price [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   99.23
Subordinated Notes [Member] | Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input   Recovery Rate
Range   65.00
Subordinated Notes [Member] | Recovery Rate [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   65.00
Subordinated Notes [Member] | Expected Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input   Expected Yield
Subordinated Notes [Member] | Expected Yield [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   11.00
Subordinated Notes [Member] | Expected Yield [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   20.50
Subordinated Notes [Member] | Expected Yield [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   15.98%
Collateralized Loan Obligations [Member] | Annual Prepayment Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input Annual Prepayment Rate  
Range 20.00  
Collateralized Loan Obligations [Member] | Annual Prepayment Rate [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 20.00  
Collateralized Loan Obligations [Member] | Reinvestment Spread [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input Reinvestment Spread  
Collateralized Loan Obligations [Member] | Reinvestment Spread [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 3.45  
Collateralized Loan Obligations [Member] | Reinvestment Spread [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 5.00  
Collateralized Loan Obligations [Member] | Reinvestment Spread [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 4.40  
Collateralized Loan Obligations [Member] | Reinvestment Price [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input Reinvestment Price  
Collateralized Loan Obligations [Member] | Reinvestment Price [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 99.50  
Collateralized Loan Obligations [Member] | Reinvestment Price [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 99.50  
Collateralized Loan Obligations [Member] | Recovery Rate [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input Recovery Rate  
Collateralized Loan Obligations [Member] | Recovery Rate [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 63.62  
Collateralized Loan Obligations [Member] | Recovery Rate [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 70.10  
Collateralized Loan Obligations [Member] | Recovery Rate [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 66.54  
Collateralized Loan Obligations [Member] | Expected Yield [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Unobservable Input Expected Yield  
Collateralized Loan Obligations [Member] | Expected Yield [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 12.78  
Collateralized Loan Obligations [Member] | Expected Yield [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 19.75  
Collateralized Loan Obligations [Member] | Expected Yield [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 15.24  
Yield Method [Member] | First Lien Senior Secured Debt [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 4,035,415 $ 2,797,561
Unobservable Input Market Yield Discount Spreads Market Yield Discount Spreads
Yield Method [Member] | First Lien Senior Secured Debt [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 3.41 3.37
Yield Method [Member] | First Lien Senior Secured Debt [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 21.5 27.84
Yield Method [Member] | First Lien Senior Secured Debt [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average 5.85 [2] 5.77 [1]
Yield Method [Member] | Second Lien Senior Secured [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value   $ 5,460
Unobservable Input   Market Yield Discount Spreads
Yield Method [Member] | Second Lien Senior Secured [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   5.18
Yield Method [Member] | Second Lien Senior Secured [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   6.18
Yield Method [Member] | Second Lien Senior Secured [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   5.68
Yield Method [Member] | Subordinated Notes [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value   $ 16,580
Unobservable Input   Market Yield Discount Spreads
Range   15.00
Yield Method [Member] | Subordinated Notes [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   15.00
Yield Method [Member] | Collateralized Loan Obligations [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 7,659  
Unobservable Input Market Yield Discount Spreads  
Yield Method [Member] | Collateralized Loan Obligations [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 7.00  
Yield Method [Member] | Collateralized Loan Obligations [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 13.00  
Yield Method [Member] | Collateralized Loan Obligations [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 9.98  
Recent Transaction [Member] | First Lien Senior Secured Debt [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 538,309 $ 102,299
Unobservable Input Transaction Price Transaction Price
Recent Transaction [Member] | First Lien Senior Secured Debt [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 88.46 98.00
Recent Transaction [Member] | First Lien Senior Secured Debt [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 100.62 100.00
Recent Transaction [Member] | First Lien Senior Secured Debt [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average 98.42 [2] 98.93 [1]
Recent Transaction [Member] | Collateralized Loan Obligations [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 35,178  
Unobservable Input Transaction Price  
Recent Transaction [Member] | Collateralized Loan Obligations [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 100.00  
Recent Transaction [Member] | Collateralized Loan Obligations [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 100.00  
Recent Transaction [Member] | Unlisted Common Stock [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 2,877  
Unobservable Input Transaction Price  
Range 589.39  
Recent Transaction [Member] | Unlisted Common Stock [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 589.39  
MarketApproach [Member] | First Lien Senior Secured Debt [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value   $ 3,554
Unobservable Input   Market Multiple
MarketApproach [Member] | First Lien Senior Secured Debt [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   0.3
MarketApproach [Member] | First Lien Senior Secured Debt [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   10.9
MarketApproach [Member] | First Lien Senior Secured Debt [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   5.6
MarketApproach [Member] | Preferred Equity [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value   $ 499
Unobservable Input   Market Multiple
MarketApproach [Member] | Preferred Equity [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   0.3
MarketApproach [Member] | Preferred Equity [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   10.9
MarketApproach [Member] | Preferred Equity [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [1]   5.6
Discounted Cash Flows [Member] | Subordinated Notes [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value   $ 32,738
Unobservable Input   Annual Default Rate
Discounted Cash Flows [Member] | Subordinated Notes [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   2.00
Discounted Cash Flows [Member] | Subordinated Notes [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range   3.00
Discounted Cash Flows [Member] | Subordinated Notes [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range [1]   2.54
Discounted Cash Flows [Member] | Collateralized Loan Obligations [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 51,598  
Unobservable Input Annual Default Rate  
Discounted Cash Flows [Member] | Collateralized Loan Obligations [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 1.73  
Discounted Cash Flows [Member] | Collateralized Loan Obligations [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 2.83  
Discounted Cash Flows [Member] | Collateralized Loan Obligations [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range [2] 2.00  
Liquidation Analysis | First Lien Senior Secured Debt [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 11,656  
Unobservable Input Recovery Rate  
Liquidation Analysis | First Lien Senior Secured Debt [Member] | Minimum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 51.97  
Liquidation Analysis | First Lien Senior Secured Debt [Member] | Maximum [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Range 89.70  
Liquidation Analysis | First Lien Senior Secured Debt [Member] | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] 74.42  
Liquidation Analysis | Preferred Equity [Member] | Residual Equity Values    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Fair Value $ 0  
Unobservable Input Residual Equity Values  
Range —  
Liquidation Analysis | Preferred Equity [Member] | Residual Equity Values | Weighted Average [Member]    
Fair Value Measurement Inputs and Valuation Techniques [Line Items]    
Weighted Average [2] —%  
[1] Weighted average is calculated by weighing the significant unobservable input by the relative fair value of each investment in the category.
[2] Weighted average is calculated by weighing the significant unobservable input by the relative fair value of each investment in the category.