Investments - 2023-1 Notes (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Debt
Total aggregate principal amount committed	$ 2,127,000	$ 2,077,000
Bain Capital Senior Loan Program, LLC
Debt
Total aggregate principal amount committed	446,000
Bain Capital Senior Loan Program, LLC \| Class A-1-R Notes
Debt
Total aggregate principal amount committed	$ 188,500
Spread rate (as a percent)	1.58%
Effective interest rate	5.26%
Bain Capital Senior Loan Program, LLC \| Class A-2-R Notes
Debt
Total aggregate principal amount committed	$ 9,750
Spread rate (as a percent)	1.80%
Effective interest rate	5.48%
Bain Capital Senior Loan Program, LLC \| Class B-R Notes
Debt
Total aggregate principal amount committed	$ 22,750
Spread rate (as a percent)	1.90%
Effective interest rate	5.58%
Bain Capital Senior Loan Program, LLC \| Class C- R Notes
Debt
Total aggregate principal amount committed	$ 8,000
Spread rate (as a percent)	2.25%
Effective interest rate	5.93%
Bain Capital Senior Loan Program, LLC \| Class D - R Notes
Debt
Total aggregate principal amount committed	$ 17,875
Spread rate (as a percent)	3.25%
Effective interest rate	6.93%
Bain Capital Senior Loan Program, LLC \| 2023-1 Notes
Debt
Total aggregate principal amount committed	$ 246,875

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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