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Other Intangible Assets (Summary of Other Intangible Assets) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Schedule of Other Intangible Assets [Abstract] |  |
Indefinite-lived intangible assets: | $ 75 | $ 76
Total other intangible assets | 85 | 86
Accumulated Amortization | 8 | 8
Syndicate capacity |  |
Schedule of Other Intangible Assets [Abstract] |  |
Indefinite-lived intangible assets: | 44 | 45
Agency force |  |
Schedule of Other Intangible Assets [Abstract] |  |
Indefinite-lived intangible assets: | 16 | 16
Insurance licenses |  |
Schedule of Other Intangible Assets [Abstract] |  |
Indefinite-lived intangible assets: | $ 15 | $ 15
Distribution channel |  |
Schedule of Other Intangible Assets [Abstract] |  |
Economic Useful Life | 15 years | 15 years
Finite-lived intangible assets: | $ 10 | $ 10
Accumulated Amortization | $ 8 | $ 8

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