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Segments of Operations - Earnings before income taxes by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2022 | Mar. 31, 2021
Segment Reporting Information [Line Items] |  |
Earnings before realized gains (losses) and income taxes | $ 376 | $ 258
Realized gains (losses) on securities | (15) | 77
Earnings from continuing operations before income taxes | 361 | 335
Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Property and casualty insurance underwriting | 207 | 134
Investment and other income, net | 215 | 154
Earnings before realized gains (losses) and income taxes | 422 | 288
Other |  |
Segment Reporting Information [Line Items] |  |
Earnings before realized gains (losses) and income taxes | (46) | (59)
Other | Continuing operations | Real estate-related entities |  |
Segment Reporting Information [Line Items] |  |
Earnings from real-estate related investments, net of DAC | 0 | 29
Property and transportation | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Property and casualty insurance underwriting | 62 | 56
Specialty casualty | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Property and casualty insurance underwriting | 124 | 56
Specialty financial | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Property and casualty insurance underwriting | 29 | 25
Other specialty | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Property and casualty insurance underwriting | (7) | (3)
Other lines | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Property and casualty insurance underwriting | $ (1) | $ 0

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