Managed Investment Entities - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($) collateralized_loan_obligation	Dec. 31, 2022 USD ($) collateralized_loan_obligation	Dec. 31, 2021 USD ($) collateralized_loan_obligation
Variable Interest Entity [Line Items]
Percentage of investment of most subordinate debt tranche, Minimum	9.00%
Percentage of investment of most subordinate debt tranche, Maximum	100.00%
Number of collateralized loan obligation entities \| collateralized_loan_obligation	12
Number of CLOs formed during the period \| collateralized_loan_obligation	1	2	1
Number of CLOs substantially liquidated during the period \| collateralized_loan_obligation	4
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments	$ 109	$ 339
Difference between aggregate unpaid principal balance and fair value of CLOs' debt	253	413
Carrying amount of CLO loans in default	7	4
Aggregate unpaid principal balance of CLO loans in default	13	17
Available for sale (AFS) fixed maturities	10,377	10,095
New collateralized loan obligation entities
Variable Interest Entity [Line Items]
Face value of liabilities issued by managed investment entities on issuance date	407	754	$ 408
Face amount of managed investment entities liabilities purchased by subsidiaries at issuance date	16	48	$ 14
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	177
New collateralized loan obligation, temporary warehousing entities
Variable Interest Entity [Line Items]
Aggregate fair value of investment in temporary warehousing entities of collateralized loan obligations	38	3
Subordinated debt obligations \| Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	106
Collateralized loan obligations
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	1,687	1,921
Collateralized loan obligations \| Managed by third parties
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	$ 1,690	$ 1,920

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Face amount of managed investment entities liabilities purchased at issuance date.

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Maximum percentage of investment of most subordinate debt tranche of variable interest entity.

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

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