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Investments - Equity securities reported at fair value (Details) - USD ($) $ in Millions | Jun. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities | $ 1,029 | $ 1,042
Common stocks |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 547 | 491
Equity securities | 569 | 586
Equity securities, fair value in excess of cost | 22 | 95
Perpetual preferred stocks |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 452 | 403
Equity securities | 460 | 456
Equity securities, fair value in excess of cost | 8 | 53
Equity securities |  |
Debt and Equity Securities, FV-NI [Line Items] |  |
Equity securities, at cost | 999 | 894
Equity securities | 1,029 | 1,042
Equity securities, fair value in excess of cost | $ 30 | $ 148

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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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