Investments (Investment Income Net of Related Expenses) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	$ 1,465	$ 1,131	$ 2,749	$ 2,131
Investment expense	(57)	(49)	(109)	(88)
Investment income, net of related expenses	1,408	1,082	2,640	2,043
Available-for-sale Securities [Member]
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	1,109	881	2,172	1,641
Equity securities
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	1	1	3	3
Mortgage Loans on Real Estate [Member]
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	128	97	247	187
Policy loans
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	12	14	30	28
Funds withheld at interest
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	68	76	134	165
Short-term Investments [Member]
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	45	44	81	78
Partnership Interest
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	103	21	88	28
Other invested assets
Major Categories Of Investment Income Net of Expenses [Line Items]
Investment revenue	$ (1)	$ (3)	$ (6)	$ 1