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v3.20.4

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | $ 5,099 | $ 5,185 | $ 4,865
Net investment income |  |  |  |  |  |  |  |  | 2,132 | 2,303 | 2,094
Other income |  |  |  |  |  |  |  |  | 204 | 223 | 223
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 7,597 | 7,950 | 7,416
Realized gains (losses) on securities |  |  |  |  |  |  |  |  | 289 | 287 | (266)
Realized gains on subsidiaries |  |  |  |  |  |  |  |  | 23 | 0 | 0
Total revenues | $ 2,623 | $ 2,060 | $ 1,951 | $ 1,275 | $ 2,130 | $ 2,123 | $ 1,960 | $ 2,024 | 7,909 | 8,237 | 7,150
Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | 5,099 | 5,185 | 4,865
Net investment income |  |  |  |  |  |  |  |  | 399 | 472 | 438
Other income |  |  |  |  |  |  |  |  | 8 | 11 | 10
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 5,506 | 5,668 | 5,313
Annuity |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net investment income |  |  |  |  |  |  |  |  | 1,699 | 1,792 | 1,638
Other income |  |  |  |  |  |  |  |  | 131 | 120 | 125
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 1,830 | 1,912 | 1,763
Other |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revenues before realized gains (losses) |  |  |  |  |  |  |  |  | 261 | 370 | 340
Property and transportation | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | 1,871 | 1,828 | 1,729
Specialty casualty | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | 2,235 | 2,597 | 2,403
Specialty financial | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | 613 | 610 | 598
Other specialty | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | 180 | 150 | 135
Other lines | Property and casualty insurance |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net earned premiums |  |  |  |  |  |  |  |  | $ 200 | $ 0 | $ 0

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