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Segments of Operations - Earnings before income taxes by segment and sub-segment (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Segment Reporting Information [Line Items] |  |  |
Earnings before realized gains (losses) and income taxes | $ 1,221 | $ 391 | $ 479
Realized gains (losses) on securities | 110 | (75) | 155
Subsidiaries | 4 | 23 | 0
Earnings from continuing operations before income taxes | 1,335 | 339 | 634
Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Property and casualty insurance underwriting | 733 | 224 | 212
Investment and other income, net | 657 | 360 | 437
Earnings before realized gains (losses) and income taxes | 1,390 | 584 | 649
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Earnings before realized gains (losses) and income taxes | (220) | (215) | (196)
Other | Real estate-related investments | Continuing operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Earnings from real-estate related investments, net of DAC | 51 | 22 | 26
Property and transportation | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Property and casualty insurance underwriting | 279 | 181 | 79
Specialty casualty | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Property and casualty insurance underwriting | 377 | 223 | 175
Specialty financial | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Property and casualty insurance underwriting | 96 | 50 | 92
Other specialty | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Property and casualty insurance underwriting | (15) | (28) | (21)
Other lines | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Property and casualty insurance underwriting | $ (4) | $ (202) | $ (113)

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