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Investments - Schedule of Contractual Maturities of Investments (Details) - USD ($) $ in Millions | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost |  |
Due in one year or less | $ 1,087 |
Due after one year through five years | 3,766 |
Due after five years through ten years | 3,955 |
Due after ten years | 8,827 |
Total | 17,635 | $ 17,033
Fair value |  |
Due in one year or less | 1,082 |
Due after one year through five years | 3,760 |
Due after five years through ten years | 3,916 |
Due after ten years | 8,419 |
Total | $ 17,177 | $ 16,480
% of fair value |  |
Due in one year or less | 6.30% |
Due after one year through five years | 21.90% |
Due after five years through ten years | 22.80% |
Due after ten years | 49.00% |
Total | 100.00% |

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