CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (PARENTHETICAL) - Related Party - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Monarch Point Re \| Loan With Monarch Point Re
Non-cash repayment of advance	$ 71	$ 48
Interest received on advance	5	6
Monarch Point Re \| Retrocession Agreement With Monarch Point Re
Reinsurance premiums	62	46
Ceded losses and loss expenses	$ 14	4
Third Party Reinsurer \| Loan Agreement With Third Party Reinsurer
Non-cash repayment of advance		25
Third Party Reinsurer \| Retrocession Agreement with Third Party Reinsurer
Reinsurance premiums		$ 25

Amount of written premiums ceded to other entities.

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Interest received on loans and other debt instruments during the current period.

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