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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, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Segment Reporting Information [Line Items] |  |  |  |
Earnings before realized gains (losses) and income taxes |  | $ 821 | $ 905 | $ 719
Realized gains (losses) on securities |  | 287 | (266) | 5
Earnings before income taxes |  | 1,108 | 639 | 724
Property and casualty insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting |  | 212 | 302 | 242
Investment and other income, net |  | 437 | 407 | 349
Earnings before realized gains (losses) and income taxes |  | 649 | 709 | 591
Annuity |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Earnings before realized gains (losses) and income taxes |  | 362 | 361 | 380
Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Earnings before realized gains (losses) and income taxes | [1] | (190) | (165) | (252)
Property and transportation | Property and casualty insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting |  | 79 | 120 | 154
Specialty casualty | Property and casualty insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting |  | 175 | 141 | 104
Specialty financial | Property and casualty insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting |  | 92 | 66 | 61
Other specialty | Property and casualty insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting |  | (21) | (5) | (2)
Other lines | Property and casualty insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting | [2] | $ (113) | $ (20) | $ (75)
[1] | Primarily holding company interest and expenses, including losses on retirement of debt of $5 million in 2019 and $51 million in 2017 and special charges to increase A&E reserves related to AFG’s former railroad and manufacturing operations ($11 million in 2019, $9 million in 2018 and $24 million in 2017).
[2] | Includes special charges to increase asbestos and environmental (“A&E”) reserves of $18 million in both 2019 and 2018 and $89 million in 2017, respectively. Also includes a $76 million charge in 2019 and $18 million in favorable development recorded in 2017 related to the Neon exited lines.

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