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v3.19.3.a.u2

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total premiums earned |  |  |  |  |  |  |  |  | $ 5,185 | $ 4,865 | $ 4,579
Net investment income |  |  |  |  |  |  |  |  | 2,303 | 2,094 | 1,831
Other income |  |  |  |  |  |  |  |  | 201 | 199 | 206
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 7,950 | 7,416 | 6,860
Realized gains (losses) on securities |  |  |  |  |  |  |  |  | 287 | (266) | 5
Total revenues | $ 2,130 | $ 2,123 | $ 1,960 | $ 2,024 | $ 1,690 | $ 2,008 | $ 1,833 | $ 1,619 | 8,237 | 7,150 | 6,865
Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total premiums earned |  |  |  |  |  |  |  |  | 5,185 | 4,865 | 4,579
Net investment income |  |  |  |  |  |  |  |  | 472 | 438 | 362
Other income |  |  |  |  |  |  |  |  | 11 | 10 | 28
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 5,668 | 5,313 | 4,969
Annuity |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  |  |  |  |  |  |  | 1,792 | 1,638 | 1,458
Other income |  |  |  |  |  |  |  |  | 108 | 107 | 103
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 1,900 | 1,745 | 1,561
Other |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 382 | 358 | 330
Property and transportation | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total premiums earned |  |  |  |  |  |  |  |  | 1,828 | 1,729 | 1,711
Specialty casualty | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total premiums earned |  |  |  |  |  |  |  |  | 2,597 | 2,403 | 2,186
Specialty financial | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total premiums earned |  |  |  |  |  |  |  |  | 610 | 598 | 576
Other specialty | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Total premiums earned |  |  |  |  |  |  |  |  | $ 150 | $ 135 | $ 106

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