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Investments (Net investment income) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Net Investment Income [Line Items] |  |  |
Gross investment income | $ 2,223 | $ 1,999 | $ 2,181
Investment expense | (64) | (64) | (63)
Net investment income | 2,159 | 1,935 | 2,118
Fixed maturity securities |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | 1,707 | 1,728 | 1,817
Equity securities |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | 83 | 65 | 85
Limited partnership investments |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | 362 | 121 | 180
Mortgage loans |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | 61 | 57 | 51
Short term investments |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | 1 | 9 | 34
Trading portfolio |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | 9 | 18 | 9
Other |  |  |
Net Investment Income [Line Items] |  |  |
Gross investment income | $ 0 | $ 1 | $ 5

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- Definition Amount, before 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://fasb.org/us-gaap/role/ref/legacyRef -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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