Investments - Other (Details) - USD ($) $ in Millions	Jun. 30, 2024	Dec. 31, 2023
Debt securities
Debt Securities, Available-for-sale [Line Items]
Assets held by insurance regulators	$ 14	$ 14

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