Investments - Schedule of Accrued Interest (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Debt Securities, Available-for-Sale [Line Items]
Accrued investment income	$ 525	$ 423
Mortgage loans
Debt Securities, Available-for-Sale [Line Items]
Accrued investment income	3	3
Bank loans, net
Debt Securities, Available-for-Sale [Line Items]
Accrued investment income	$ 5	$ 3

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