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Investments and Cash - Equity in Net Earnings of Investees (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Net Investment Income [Line Items] |  |  |
Equity in earnings (losses) of investees | $ (39) | $ 94 | $ 27
Fair Value Measured at Net Asset Value |  |  |
Net Investment Income [Line Items] |  |  |
Equity in earnings (losses) of investees |  | 36 | 14
Equity Securities |  |  |
Net Investment Income [Line Items] |  |  |
Equity in earnings (losses) of investees | (39) | 94 | 27
Cash dividends from subsidiaries | 10 | 15 | 10
Equity Securities | AssuredIM Funds |  |  |
Net Investment Income [Line Items] |  |  |
Equity in earnings (losses) of investees | 2 | 30 | 14
Equity Securities | Other |  |  |
Net Investment Income [Line Items] |  |  |
Equity in earnings (losses) of investees | $ (41) | $ 64 | $ 13

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