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Investments - Equity securities reported at fair value (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities | $ 1,008 | $ 1,010
Common stocks |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 595 | 556
Equity securities | 579 | 553
Equity securities, fair value in excess of cost | (16) | (3)
Perpetual preferred stocks |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 434 | 436
Equity securities | 429 | 457
Equity securities, fair value in excess of cost | (5) | 21
Equity securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 1,029 | 992
Equity securities | 1,008 | 1,010
Equity securities, fair value in excess of cost | $ (21) | $ 18

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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI) in excess of the cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. + References No definition available. + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI https://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740 + Details
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