Reinsurance - Rollforward of the Reinsurance Recoverable Allowance for Credit Losses (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of year	$ 269	$ 255	$ 260
Addition to (release of) allowance for expected credit losses and disputes, net	28	11	(5)
Write-offs charged against the allowance for credit losses and disputes	(4)	(1)	0
Other changes	4	4	0
Balance, end of year	$ 297	$ 269	$ 255