Fair Value - Fair Value Option (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ 351	$ (961)
Mortgage loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	296	(916)
Unpaid principal balance	35,974		$ 33,653
Mark to fair value	(2,582)		(2,842)
Fair value	33,392		30,811
Fair Value, Option, Credit Risk, Gains (Losses) on Assets	(3)	(18)
Future policy benefits
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	(47)	0
Residential mortgage loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option, loans, 90 days or more past due	433		472
Fair Value, Option, Loans Held as Assets, Aggregate Amount in Nonaccrual Status	234		360
Unpaid principal balance	483		522
Fair value	433		472
Fair Value, Option, Loans Held as Assets, Aggregate Difference	(50)		(50)
Residential mortgage loans \| Loans Insured or Guaranteed by US Government Authorities
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option, loans, 90 days or more past due	199		221
Mortgage loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option, loans, 90 days or more past due	11		2
Fair Value, Option, Loans Held as Assets, Aggregate Amount in Nonaccrual Status	131		19
Unpaid principal balance	198		74
Fair value	142		19
Fair Value, Option, Loans Held as Assets, Aggregate Difference	(56)		$ (55)
Investment related gains (losses) \| Trading securities
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	64	(207)
Net investment income \| Investment funds
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	64	20
Future policy and other policy benefits \| Future policy benefits
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ (26)	$ 142

Fair Value, Option, Fair Value Carrying Amount, Assets

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- Definition

Fair Value, Option, Unpaid Principal Balance, Assets

+ References

No definition available.

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- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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This item represents the estimated amount of gains or losses included in earnings during the period attributable to changes in instrument-specific credit risk arising from loans and other receivables held as assets.

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-Publisher FASB
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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

This item represents the aggregate fair value of loans held as assets that are in nonaccrual status for which the fair value option has been elected, if the entity's policy is to recognize interest income separately from other changes in fair value.

+ References

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- Definition

For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due, in nonaccrual status, or both.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Section 50
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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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