Investments (Net Investment Income) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Income [Line Items]
Gross Investment Income, Operating	$ 3,372	$ 3,119	$ 6,792	$ 6,293
Less: Investment expenses	358	313	678	611
Net investment income	3,014	2,806	6,114	5,682
Fixed Maturity Securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	2,116	1,897	4,160	3,765
Mortgage loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	712	743	1,429	1,506
Policy loans
Net Investment Income [Line Items]
Gross Investment Income, Operating	72	71	145	141
Real Estate and Real Estate Joint Ventures
Net Investment Income [Line Items]
Gross Investment Income, Operating	185	170	346	299
Other limited partnership interests
Net Investment Income [Line Items]
Gross Investment Income, Operating	(4)	27	179	140
Cash, cash equivalents and short-term investments
Net Investment Income [Line Items]
Gross Investment Income, Operating	83	79	173	169
FVO Securities [Member]
Net Investment Income [Line Items]
Gross Investment Income, Operating	141	81	101	48
Net investment income	125	81	85	46
Operating joint venture
Net Investment Income [Line Items]
Gross Investment Income, Operating	50	32	68	48
Equity securities
Net Investment Income [Line Items]
Gross Investment Income, Operating	1	0	2	4
Other than Securities Investment
Net Investment Income [Line Items]
Net investment income	$ 16	$ 19	$ 189	$ 173

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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