Investments (Narrative) (Detail) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Investments [Line Items]
Restricted assets in fixed maturities and short-term investments	$ 16,021	$ 15,721
Restricted assets in cash	94	$ 115
Investments
Investments [Line Items]
Deferred Tax Assets, Valuation Allowance	$ 646

[Line Items] for This table lists the investments. The line items identify information about all investments.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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- Definition

Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- Definition

Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

+ References

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