Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Net Investment Income [Line Items]
Gross investment income	$ 1,362	$ 1,262	$ 2,671	$ 2,388
Less: Investment expenses	86	90	172	181
Net investment income	1,276	1,172	2,499	2,207
Fixed maturity securities
Net Investment Income [Line Items]
Gross investment income	928	861	1,836	1,691
Equity securities
Net Investment Income [Line Items]
Gross investment income	0	1	2	1
Mortgage loans
Net Investment Income [Line Items]
Gross investment income	250	237	495	475
Policy loans
Net Investment Income [Line Items]
Gross investment income	14	13	23	22
Limited partnerships and LLCs
Net Investment Income [Line Items]
Gross investment income	98	89	172	76
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross investment income	47	43	94	83
Other assets
Net Investment Income [Line Items]
Gross investment income	$ 25	$ 18	$ 49	$ 40

Amount, before investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments.

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