Equity method investment, additional 38.7 percentage obtained

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Investments (Narrative) (Detail) $ in Millions	12 Months Ended
Investments (Narrative) (Detail) $ in Millions	Dec. 31, 2022	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) partnerships
Investment [Line Items]
Document Period End Date		Dec. 31, 2021
Limited partnerships number \| partnerships			130
Restricted assets in fixed maturities and short-term investments		$ 17,092	$ 19,605
Restricted assets in cash		$ 152	$ 89
CHINA \| Huatai Group [Member]
Investment [Line Items]
Ownership Percentage		47.00%	47.00%
CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage		20.00%	20.00%
Subsequent Event [Member] \| CHINA \| Huatai Group [Member]
Investment [Line Items]
Equity method investment, additional 7.1 percentage obtained	38.70%
Indirect Ownership [Member] \| CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage		37.70%
Direct Ownership [Member] \| CHINA \| Huatai Group [Member]
Investment [Line Items]
Ownership Percentage		47.30%
Direct Ownership [Member] \| CHINA \| Huatai Life Insurance Co. [Member]
Investment [Line Items]
Ownership Percentage		20.00%