Investments - Geographic composition of investments based on fair value (Details)	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Investments
Total	100.00%	100.00%
U.S.
Investments
Total	95.60%	96.60%
Non-U.S.
Investments
Total	4.40%	3.40%

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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+ Details