Net Investment Income (Detail) - 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 before expenses and fees	$ 833	$ 809	$ 1,638	$ 1,618
Expenses and fees	(25)	(24)	(48)	(46)
Net investment income	808	785	1,590	1,572
Fixed maturity securities—taxable
Net Investment Income [Line Items]
Gross investment income before expenses and fees	571	567	1,125	1,128
Fixed maturity securities—non-taxable
Net Investment Income [Line Items]
Gross investment income before expenses and fees	0	1	1	2
Equity Securities
Net Investment Income [Line Items]
Gross investment income before expenses and fees	3	3	5	5
Commercial mortgage loans
Net Investment Income [Line Items]
Gross investment income before expenses and fees	75	75	150	151
Policy Loans
Net Investment Income [Line Items]
Gross investment income before expenses and fees	56	54	114	109
Limited partnerships
Net Investment Income [Line Items]
Gross investment income before expenses and fees	36	17	56	45
Other invested assets
Net Investment Income [Line Items]
Gross investment income before expenses and fees	67	70	135	138
Cash, cash equivalents, restricted cash and short-term investments
Net Investment Income [Line Items]
Gross investment income before expenses and fees	$ 25	$ 22	$ 52	$ 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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Amount of expenses related to the generation of investment income.

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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.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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