Shareholders' Equity - Reclassifications from Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net realized losses	$ (2)	$ (6)
Reclassification out of Accumulated Other Comprehensive Income \| Unrealized losses on fixed maturities, AFS
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net realized losses	$ (2)	$ (6)

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