Deferred Acquisition Costs and Other Actuarial Balances - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Long-duration and short-duration insurance
Deferred Acquisition Costs
Amortization of deferred acquisition costs	$ 100.7	$ 98.7	$ 200.5	$ 197.2

Amount of amortization expense (reversal of expense) for deferred policy acquisition costs.

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+ Details