Unpaid Claims and Claims Expense Short Duration Contracts (Rollforward Of Claims) (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward]
Liability for Claims and Claims Adjustment Expense	$ 3,016	$ 2,769	$ 2,693	$ 2,730
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	(60)	(69)	(53)	(80)
Liability For Unpaid Claims And Claims Adjustment Expense Net Of Recoverable	2,956	2,700	$ 2,640	$ 2,650
Current Year Claims and Claims Adjustment Expense	1,123	771
Prior Year Claims and Claims Adjustment Expense	47	55
Liability for Unpaid Claims and Claims Adjustment Expense, Incurred Claims	1,170	716
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Current Year	(163)	(107)
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid, Prior Years	(779)	(532)
Liability for Unpaid Claims and Claims Adjustment Expense, Claims Paid	(942)	(639)
Interest On Liability For Policy And Contract Claims	17	19
Liability for Unpaid Claims and Claims Adjustment Expense, Foreign Currency Translation Gain (Loss)	71	(46)
Liability for Unpaid Claims and Claims Adjustment Expense Other	$ (88)	$ (27)