F&G Reinsurance - Schedule of Assets Held in Support of Reserves Associated with Coinsurance with Funds Withheld Agreement (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	$ 17,457	$ 14,191
Funds Held under Reinsurance Agreements, Liability	(17,457)	(14,191)
Fixed maturities, AFS
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	15,013	12,530
Equity securities
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	60	60
Derivative instruments
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	143	55
Mortgage loans
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	576	65
Investments in unconsolidated affiliates
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	954	752
Policy loans
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	1	1
Cash and cash equivalents
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	528	702
Subtotal
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	17,275	14,165
Accrued interest receivable, included in Prepaid expenses and other assets
Effects of Reinsurance [Line Items]
Funds withheld for reinsurance receivable, at fair value	235	146
Accounts payable and accrued liabilities and reconciling items
Effects of Reinsurance [Line Items]
Funds Held under Reinsurance Agreements, Liability	$ (53)	$ (120)

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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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.

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

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