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Goodwill and Other Intangible Assets - Schedule of Finite-lived Intangible Assets (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Finite-Lived Intangible Assets [Line Items] |  |
Goodwill | $ 0 | $ 117
Finite-lived intangible assets, gross | 1 | 82
Accumulated amortization | (1) | (42)
Finite-lived intangible assets, net | 0 | 40
Indefinite-lived intangible assets (insurance licenses) | 6 | 6
Total goodwill and other intangible assets | 6 | 163
Assured IM |  |
Finite-Lived Intangible Assets [Line Items] |  |
Total goodwill and other intangible assets | $ 0 |
CLO Contracts |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross |  | $ 42
CLO Contracts | Minimum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Useful life |  | 1 year 2 months 12 days
Investment Management Contracts |  |
Finite-Lived Intangible Assets [Line Items] |  |
Finite-lived intangible assets, gross |  | $ 24
Investment Management Contracts | Maximum |  |
Finite-Lived Intangible Assets [Line Items] |  |
Useful life |  | 6 years 9 months 18 days

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