Segments of Operations - Assets by segment (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Total assets	$ 29,787	$ 28,831
Property and casualty insurance
Segment Reporting Information [Line Items]
Total assets	24,475	22,225
Other
Segment Reporting Information [Line Items]
Total assets	$ 5,312	$ 6,606

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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+ Details