Schedule V (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Allowance for premiums and insurances balances receivable
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, Beginning of year	$ 138	$ 168	$ 184
Charged to Costs and Expenses	1	(7)	0
Write Offs	(12)	(28)	(15)
Other Changes	0	5	(1)
Balance, End of year	127	138	168
Federal and foreign valuation allowance for deferred tax assets
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, Beginning of year	1,745	2,594	1,890
Charged to Costs and Expenses	(31)	(365)	(174)
Write Offs	0	0	0
Other Changes	(64)	(484)	878
Balance, End of year	$ 1,650	$ 1,745	$ 2,594