Fair Value of Financial Instruments - Additional Information (Detail) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 55,027	$ 60,480
GMWB non-performance risk impact	$ 42	49
Period end valuation	0
Fixed maturity securities
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 55,027	60,480
Fixed maturity securities \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	31,823	34,924
Fixed maturity securities \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	9,453	10,535
Level 2
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	51,498	56,672
Level 2 \| Fixed maturity securities \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	29,554	32,543
Level 2 \| Fixed maturity securities \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 8,413	9,373
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	$ 27,876
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	7,414
Level 2 \| Fixed maturity securities \| Internal models \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	1,678
Level 2 \| Fixed maturity securities \| Internal models \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	999
Level 3
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	3,529	3,808
Level 3 \| Fixed maturity securities \| U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	2,269	2,381
Level 3 \| Fixed maturity securities \| Non-U.S. corporate
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	1,040	$ 1,162
Level 3 \| Fixed maturity securities \| Internal models
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	3,260
Level 3 \| Fixed maturity securities \| Broker Quotes
Fair Value of Financial Instruments [Line Items]
Available-for-sale debt securities	$ 269
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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- Definition

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
-Section S99
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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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-Section 50
-Paragraph 6A
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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