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Investments - Schedule of Contractual Maturities of Investments (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost |  |
Due in one year or less | $ 1,225 |
Due after one year through five years | 3,802 |
Due after five years through ten years | 3,832 |
Due after ten years | 8,250 |
Total | 17,109 | $ 17,033
Fair value |  |
Due in one year or less | 1,222 |
Due after one year through five years | 3,774 |
Due after five years through ten years | 3,759 |
Due after ten years | 7,868 |
Total | $ 16,623 | $ 16,480
% of fair value |  |
Due in one year or less | 7.40% |
Due after one year through five years | 22.70% |
Due after five years through ten years | 22.60% |
Due after ten years | 47.30% |
Total | 100.00% |

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