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Investments - Equity securities reported at fair value (Details) - USD ($) $ in Millions | Jun. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities | $ 1,077 | $ 1,018
Common stocks |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 558 | 512
Equity securities | 655 | 586
Equity securities, fair value in excess of cost | 97 | 74
Perpetual preferred stocks |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 389 | 422
Equity securities | 422 | 432
Equity securities, fair value in excess of cost | 33 | 10
Equity securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 947 | 934
Equity securities | 1,077 | 1,018
Equity securities, fair value in excess of cost | $ 130 | $ 84

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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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