Investments - Schedule of Carrying Value for Limited Partnership Interests (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Debt and Equity Securities, FV-NI [Line Items]
Total	$ 9,213	$ 9,255
Private equity
Debt and Equity Securities, FV-NI [Line Items]
Total	7,515	7,734
Real estate
Debt and Equity Securities, FV-NI [Line Items]
Total	1,466	1,236
Other
Debt and Equity Securities, FV-NI [Line Items]
Total	$ 232	$ 285

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6B

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