Fair Value of Financial Instruments - Additional Information (Detail) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 60,480	$ 63,495
GMWB non-performance risk impact	$ 49	66
Period end valuation	0
Fixed maturity securities
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 60,480	63,495
Fixed maturity securities \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	34,924	35,857
Fixed maturity securities \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	10,535	10,811
Level 2
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	56,672	59,406
Level 2 \| Fixed maturity securities \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	32,543	33,585
Level 2 \| Fixed maturity securities \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 9,373	9,203
Level 2 \| Fixed maturity securities \| Third-Party Pricing Services
Fair Value of Financial Instruments [Line Items]
Percentage of available for sale debt securities	89.00%
Level 2 \| Fixed maturity securities \| Third-Party Pricing Services \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 30,774
Level 2 \| Fixed maturity securities \| Third-Party Pricing Services \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	8,322
Level 2 \| Fixed maturity securities \| Internal models \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	1,769
Level 2 \| Fixed maturity securities \| Internal models \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	1,051
Level 3
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	3,808	4,089
Level 3 \| Fixed maturity securities \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	2,381	2,272
Level 3 \| Fixed maturity securities \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	1,162	$ 1,608
Level 3 \| Fixed maturity securities \| Internal models
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	3,496
Level 3 \| Fixed maturity securities \| Broker Quotes
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 312
Fair Value Measured at Net Asset Value Per Share \| Limited Partnerships \| Maximum
Fair Value of Financial Instruments [Line Items]
Liquidation period	10 years
Contractual period	12 years
Fair Value Measured at Net Asset Value Per Share \| Limited Partnerships \| Minimum
Fair Value of Financial Instruments [Line Items]
Liquidation period	5 years
Contractual period	10 years

Fair Value of Financial Instruments [Line Items]

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- Definition

This item represents the decrease in fair value of GMWB liabilities during the period due to the impact of non-performance risk.

+ References

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Percent of total fixed maturity securities portfolio priced using third-party pricing sources in determining fair value.

+ References

No definition available.

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- Definition

The valuation of financial futures at the end of the period as a result of settling the margins on these contracts on a daily basis.

+ References

No definition available.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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Remaining period of expected liquidation by investee of underlying asset of investment measured at net asset value per share or unit. In 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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Period when redemption restriction has been in effect for investments for which net asset value per share is calculated (including by unit, membership interest, or other equity (ownership interest) unit measure), in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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