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Segments of Operations - Narrative (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) segment | Jun. 30, 2020 USD ($)
Segment Reporting Information [Line Items] |  |  |  |
Number of segments | segment |  |  | 2 |
Net investment income | $ 164 | $ 88 | $ 352 | $ 192
Neon Capital Limited |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income |  | 0 |  | (6)
Neon Capital Limited | Maximum |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income |  | 1 |  |
Continuing operations |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Earnings from real-estate related investments, net of DAC | 22 | 2 | 51 | 8
Continuing operations | Real estate-related investments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income | 22 | 7 | 51 | 19
Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income | 143 | 72 | 302 | 165
Property and casualty insurance underwriting | 152 | 9 | 286 | 96
Investment and other income, net | 136 | 65 | 290 | 149
Other lines | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting | $ (1) | (45) | $ (1) | (47)
Other lines | Property and Casualty Insurance | Neon Capital Limited |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Property and casualty insurance underwriting |  | (43) |  | (44)
Investment and other income, net |  | (1) |  | (10)
Neon Capital Limited | Other lines | Property and Casualty Insurance |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income |  |  |  | $ (6)
Neon Capital Limited | Other lines | Property and Casualty Insurance | Maximum |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Net investment income |  | $ 1 |  |

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- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + Details
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