Investments (Schedule Of Sources Of Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Investment Income [Line Items]
Gross investment income	$ 5,132	$ 3,920	$ 3,643
Investment expenses	(195)	(178)	(187)
Net investment income	4,937	3,742	3,456
Amortization of Debt Issuance Costs and Discounts	(21)	(41)	(84)
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	4,619	3,594	3,300
Short-term investments
Net Investment Income [Line Items]
Gross investment income	199	81	35
Other interest income
Net Investment Income [Line Items]
Gross investment income	69	42	11
Equity securities
Net Investment Income [Line Items]
Gross investment income	119	99	150
Private equities
Net Investment Income [Line Items]
Gross investment income	55	63	94
Other Investments
Net Investment Income [Line Items]
Gross investment income	$ 71	$ 41	$ 53