Investments - Schedule of Carrying Value for Limited Partnership Interests (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Debt and Equity Securities, FV-NI [Line Items]
Total	$ 9,058	$ 8,844
Private equity
Debt and Equity Securities, FV-NI [Line Items]
Total	7,140	7,247
Real estate
Debt and Equity Securities, FV-NI [Line Items]
Total	1,651	1,451
Other investments
Debt and Equity Securities, FV-NI [Line Items]
Total	$ 267	$ 146

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