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Investments in Fixed Maturity Securities (Narrative) (Details) $ in Millions | Dec. 31, 2022 USD ($)
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Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items] |
Debt Securities, Held-to-maturity, Restricted | $ 1,218
Insurance |
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items] |
Debt Securities, Held-to-maturity, Restricted | 656
Reinsurance & Monoline Excess |
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items] |
Debt Securities, Held-to-maturity, Restricted | 31
Letters of Credit Outstanding, Amount | 5
523991 Trust, Fiduciary, and Custody Activities |
Schedule of Available-for-sale and Held-to-maturity Securities [Table] [Line Items] |
Debt Securities, Held-to-maturity, Restricted | $ 1,910

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