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Investments - Narrative (Details) $ in Millions	Mar. 31, 2023 USD ($) security	Dec. 31, 2022 USD ($)
Schedule of Investments [Line Items]
Unfunded commitments to limited partnerships	$ 412	$ 396
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	94.00%
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade	95.00%
Multifamily
Schedule of Investments [Line Items]
Percent of real-estate related investments by property type	92.00%	92.00%
Fixed maturities
Schedule of Investments [Line Items]
Gross unrealized losses on fixed maturities	$ 577	$ 669
Number of available for sale securities in an unrealized loss position | security	1,700,000,000

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Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade.

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Represents commitments to fund credit facilities and contribute capital to certain limited partnership investments at a future date.

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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