Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Net Investment Income [Line Items]
Less: Investment expenses	$ 527	$ 564	$ 1,053	$ 1,132
Net investment income	5,661	5,205	10,546	10,641
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	5,690	5,550	11,328	11,012
Net investment income	5,163	4,986	10,275	9,880
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,608	3,355	7,075	6,643
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	3	7	12	14
FVO securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	107	22	87	107
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,104	1,187	2,243	2,381
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	113	110	220	223
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	239	80	446	90
OLPI
Net Investment Income [Line Items]
Gross Investment Income, Operating	124	325	344	626
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	254	250	504	541
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	38	22	58	44
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	100	192	339	343
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 498	$ 219	$ 271	$ 761

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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Amount, after 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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