Investments - Amortized Cost of Mortgage Loans on Real Estate on Nonaccrual Status (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Financing Receivable, Nonaccrual [Line Items]
Amortized cost of mortgage loans on real estate on nonaccrual status	$ 134	$ 96
Commercial mortgage loans on real estate
Financing Receivable, Nonaccrual [Line Items]
Amortized cost of mortgage loans on real estate on nonaccrual status	6	4
Residential mortgage loans on real estate
Financing Receivable, Nonaccrual [Line Items]
Amortized cost of mortgage loans on real estate on nonaccrual status	$ 128	$ 92

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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+ Details