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v3.21.1

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Segment Reporting Information [Line Items] |  |
Net earned premiums | $ 1,173 | $ 1,209
Net investment income | 188 | 104
Other income | 23 | 24
Revenues before realized gains (losses) | 1,432 | 1,383
Realized gains (losses) on securities | 77 | (328)
Total revenues | 1,509 | 1,055
Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Net earned premiums | 1,173 | 1,209
Net investment income | 159 | 93
Other income | 4 | 5
Revenues before realized gains (losses) | 1,336 | 1,307
Other |  |
Segment Reporting Information [Line Items] |  |
Revenues before realized gains (losses) | 96 | 76
Specialty Property and transportation | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Net earned premiums | 394 | 386
Specialty casualty | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Net earned premiums | 571 | 556
Specialty financial | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Net earned premiums | 157 | 156
Other specialty | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Net earned premiums | 51 | 40
Other lines | Property and Casualty Insurance |  |
Segment Reporting Information [Line Items] |  |
Net earned premiums | $ 0 | $ 71

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