Investments - Summary of Sources of Collateral Received and Various Investment Agreement in which Collateral Pledged (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Investment [Line Items]
Fair Value Of Securities Deposited With Governmental Authorities	$ 27	$ 24
Fair Value of Securities Deposited in Connection wtih Letter of Credit	$ 1	$ 1

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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