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v3.24.0.1

Segments of Operations - Revenues by segment and sub-segment (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | $ 6,531 | $ 6,085 | $ 5,404
Net investment income | 742 | 717 | 730
Other income | 146 | 117 | 113
Revenues before realized gains (losses) | $ 7,867 | $ 7,156 | $ 6,438
Investment, Type [Extensible Enumeration] | Real Estate Funds [Member] | Real Estate Funds [Member] | Real Estate Funds [Member]
Realized gains (losses) on securities | $ (36) | $ (116) | $ 110
Realized gains (losses) on subsidiaries | (4) | 0 | 4
Total revenues | 7,827 | 7,040 | 6,552
Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 6,531 | 6,085 | 5,404
Net investment income | 729 | 683 | 663
Other income | 16 | 12 | 27
Revenues before realized gains (losses) | 7,276 | 6,780 | 6,094
Other |  |  |
Segment Reporting Information [Line Items] |  |  |
Revenues before realized gains (losses) | 591 | 376 | 293
Other | Continuing operations |  |  |
Segment Reporting Information [Line Items] |  |  |
Net investment income | 0 | 0 | 51
Property and transportation | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 2,519 | 2,487 | 2,144
Specialty casualty | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 2,886 | 2,659 | 2,408
Specialty financial | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | 867 | 698 | 642
Other specialty | Property and casualty insurance |  |  |
Segment Reporting Information [Line Items] |  |  |
Net earned premiums | $ 259 | $ 241 | $ 210

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