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Managed Investment Entities - Narrative (Details)	9 Months Ended
	Sep. 30, 2025 USD ($) collateralized_loan_obligation	Sep. 30, 2024 USD ($) collateralized_loan_obligation	Dec. 31, 2024 USD ($)
Variable Interest Entity [Line Items]
Percentage of investment of most subordinate debt tranche, Minimum	5.40%
Percentage of investment of most subordinate debt tranche, Maximum	100.00%
Number of collateralized loan obligation entities | collateralized_loan_obligation	12
Number of collateralized loan obligation entities formed during the period | collateralized_loan_obligation	2	2
Number of collateralized loan obligation entities substantially liquidated during the period | collateralized_loan_obligation	3
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments	$ 73,000,000		$ 66,000,000
Difference between aggregate unpaid principal balance and carrying value of CLOs' debt	218,000,000		172,000,000
Carrying amount of CLO loans in default	0		3,000,000
Aggregate unpaid principal balance of variable interest entity loans in default			5,000,000
Available for sale (AFS) fixed maturities	10,518,000,000		10,398,000,000
Collateralized loan obligations
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	1,100,000,000		1,237,000,000
Managed by third parties | Collateralized loan obligations
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	1,100,000,000		$ 1,240,000,000
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Investment in CLO tranches	138,000,000
Variable interest entity, primary beneficiary | Subordinated debt obligations
Variable Interest Entity [Line Items]
Investment in CLO tranches	116,000,000
New collateralized loan obligation, temporary warehousing entities
Variable Interest Entity [Line Items]
Investment in CLO tranches	8,000,000
New collateralized loan obligation entities
Variable Interest Entity [Line Items]
Face value of liabilities issued by managed investment entities on issuance date	813,000,000	$ 813,000,000
Face amount of managed investment entities liabilities purchased at issuance date	$ 80,000,000	$ 73,000,000

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