Reinsurance - Narrative (Details) - USD ($) $ in Billions	Sep. 30, 2026	Dec. 31, 2025
Effects of Reinsurance [Line Items]
Ceded reserves	$ 3.0
Reinsurance recoverables	$ 40.1	$ 40.7
Investment Grade
Effects of Reinsurance [Line Items]
Reinsurance recoverable (as a percent)	80.00%	80.00%
Non-Investment Grade
Effects of Reinsurance [Line Items]
Reinsurance recoverable (as a percent)	17.00%	17.00%
Non-Investment Grade \| Captive Insurers
Effects of Reinsurance [Line Items]
Reinsurance recoverable (as a percent)	90.00%	87.00%
Not Rated
Effects of Reinsurance [Line Items]
Reinsurance recoverable (as a percent)	3.00%	3.00%

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

- Definition

Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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