Investments - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Short-term investments	$ 4,318	$ 5,144
Accrued investment income	567	539
Fixed income securities
Debt Securities, Available-for-Sale [Line Items]
Accrued investment income	$ 527	$ 495

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
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+ Details