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Investments (Narrative) (Details) $ in Millions | Dec. 31, 2023 USD ($) security | Dec. 31, 2022 USD ($) security | Dec. 31, 2021 USD ($) security
--- | --- | --- | ---
Gain (Loss) on Investments |  |  |
Assets Held by Insurance Regulators | $ 108 | $ 107 |
Collateral at fair value | 125 | 135 |
Fair Value of Owned Common Equities Held in Trust Account | 107 | 101 |
Equity Securities at Fair Value | 10,989 | 9,841 |
Largest single common stock holding | $ 842 | $ 597 |
Largest equity holdings to total equity portfolio | 7.90% | 6.30% |
Largest equity holdings to total portfolio | 3.40% | 2.70% |
Debt Securities, Available-for-Sale, Allowance for Credit Loss | $ 18 | $ 1 | $ 1
Fixed Maturities |  |  |
Gain (Loss) on Investments |  |  |
Number Of Securities Continuous Unrealized Loss Position | security | 2,840 | 3,272 | 278
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss 3 | $ 687 | $ 908 | $ 16
Number of securities below 70 percent of amortized cost | 20 | 49 | 0

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