Investments (Schedule Of Sources Of Net Investment Income) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Net Investment Income [Line Items]
Gross investment income	$ 3,920	$ 3,643	$ 3,551
Investment expenses	(178)	(187)	(176)
Net investment income	3,742	3,456	3,375
Amortization of Debt Issuance Costs and Discounts	(41)	(84)	(116)
Fixed maturities
Net Investment Income [Line Items]
Gross investment income	3,594	3,300	3,321
Short-term investments
Net Investment Income [Line Items]
Gross investment income	81	35	48
Other interest income
Net Investment Income [Line Items]
Gross investment income	42	11	19
Equity securities
Net Investment Income [Line Items]
Gross investment income	99	150	81
Other Investments
Net Investment Income [Line Items]
Gross investment income	$ 104	$ 147	$ 82

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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