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Investments (Net realized investment gains (losses)) (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023 | Sep. 30, 2022
Fixed maturity securities: |  |  |  |
Gross gains | $ 12,000,000 | $ 23,000,000 | $ 55,000,000 | $ 94,000,000
Gross losses | (49,000,000) | (134,000,000) | (141,000,000) | (222,000,000)
Net investment gains (losses) on fixed maturity securities | (37,000,000) | (111,000,000) | (86,000,000) | (128,000,000)
Equity securities | 2,000,000 | (2,000,000) | (9,000,000) | (111,000,000)
Derivatives | 0 | 24,000,000 | 0 | 79,000,000
Mortgage loans | (5,000,000) | (8,000,000) | (11,000,000) | (8,000,000)
Short term investments and other | 2,000,000 | 1,000,000 | 1,000,000 | 2,000,000
Net investment gains (losses) | (38,000,000) | (96,000,000) | (105,000,000) | (166,000,000)
Non-redeemable preferred stock |  |  |  |
Fixed maturity securities: |  |  |  |
Net investment income (loss) recognized due to the change in fair value of common stock held as of September 30, 2023 and 2022 | $ 2,000,000 | $ (2,000,000) | $ 2,000,000 | $ (109,000,000)

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- Definition Realized Gain (Loss) On Short Term Investments + References No definition available. + Details
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- Definition Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-9 + Details
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- Definition Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-9 + Details
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- Definition Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(3)(d)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483586/944-220-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 321 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479536/321-10-50-4 + Details
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