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Segment information Segment Information (narrative Detail (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |  |
Gain (Loss) on Derivative |  | $ 160 | $ (123) | $ (223) | $ 424
Net investment income |  | 884 | 827 | 1,747 | 1,688
Gains(Losses) On Fair Value Changes In Separate Account Assets | [1] | (15) | (40) | (19) | 16
North America Agricultural Insurance [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net investment income |  | 8 | 7 | 15 | 16
Segment Life [Member] |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Net investment income |  | $ 101 | $ 95 | $ 199 | $ 190
[1] | Related to gains (losses) from fair value changes in separate account assets that do not qualify for separate account reporting under GAAP.

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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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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