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]
Less: Investment expenses	$ 564	$ 681	$ 1,132	$ 1,142
Net investment income	5,205	5,072	10,641	9,717
Securities Investment
Net Investment Income [Line Items]
Gross Investment Income, Operating	5,550	5,458	11,012	10,260
Net investment income	4,986	4,777	9,880	9,118
Fixed maturity securities AFS
Net Investment Income [Line Items]
Gross Investment Income, Operating	3,355	3,228	6,643	6,367
Equity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	7	10	14	22
FVO securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	22	50	107	98
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	1,187	1,306	2,381	2,347
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	110	119	223	238
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	80	137	90	163
OLPI
Net Investment Income [Line Items]
Gross Investment Income, Operating	325	225	626	250
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	250	248	541	465
Operating joint ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	22	13	44	32
Other Investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	192	122	343	278
Unit-linked investments
Net Investment Income [Line Items]
Net investment income	$ 219	$ 295	$ 761	$ 599

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