Reinsurance - Schedule of Assets Held in Support of Reserves Associated with Coinsurance with Funds Withheld Agreement (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	$ 17,907	$ 14,165
Funds withheld for reinsurance liabilities	(17,837)	(14,191)
Net assets	17,837	14,191
Fixed maturities, AFS
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	15,312	12,530
Equity securities
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	60	60
Derivative instruments
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	146	55
Mortgage loans
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	781	65
Investments in unconsolidated affiliates
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	1,006	752
Policy loans
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	1	1
Cash and cash equivalents
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	601	702
Accrued interest receivable, included in Prepaid expenses and other assets
Effects of Reinsurance
Funds withheld for reinsurance receivable, at fair value	189	146
Accounts payable and accrued liabilities and reconciling items
Effects of Reinsurance
Funds withheld for reinsurance liabilities	$ (259)	$ (120)

Funds Held under Reinsurance Agreements, Asset, Net of Adjustments

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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.

+ References

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- Definition

Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount of funds held as security for payments to be received under reinsurance contracts.

+ References

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