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Securities - Scheduled Contractual Maturities of AFS (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Amortized cost |  |
Within One Year | $ 185,142 |
After One Year through Five Years | 861,917 |
After Five Years through Ten Years | 771,030 |
After Ten Years | 8,849,204 |
Amortized Cost | 10,667,293 | $ 6,916,491
Fair value |  |
Within One Year | 183,256 |
After One Year through Five Years | 825,144 |
After Five Years through Ten Years | 697,704 |
After Ten Years | 8,427,773 |
Total | $ 10,133,877 |
Weighted Average Yield |  |
Within One Year | 3.11% |
After One Year through Five Years | 1.47% |
After Five Years through Ten Years | 3.38% |
After Ten Years | 4.95% |
Total | 4.52% |
U.S. Treasury securities |  |
Amortized cost |  |
Within One Year | $ 59,430 |
After One Year through Five Years | 616,864 |
After Five Years through Ten Years | 0 |
After Ten Years | 0 |
Amortized Cost | 676,294 |
Fair value |  |
Within One Year | 58,770 |
After One Year through Five Years | 582,803 |
After Five Years through Ten Years | 0 |
After Ten Years | 0 |
Total | $ 641,573 |
Weighted Average Yield |  |
Within One Year | 2.15% |
After One Year through Five Years | 1.12% |
After Five Years through Ten Years | 0.00% |
After Ten Years | 0.00% |
Total | 1.21% |
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Amortized cost |  |
Within One Year | $ 17,972 |
After One Year through Five Years | 27,030 |
After Five Years through Ten Years | 176,548 |
After Ten Years | 87,727 |
Amortized Cost | 309,277 |
Fair value |  |
Within One Year | 17,459 |
After One Year through Five Years | 25,738 |
After Five Years through Ten Years | 154,620 |
After Ten Years | 74,631 |
Total | $ 272,448 |
Weighted Average Yield |  |
Within One Year | 1.06% |
After One Year through Five Years | 1.13% |
After Five Years through Ten Years | 1.92% |
After Ten Years | 2.17% |
Total | 1.88% |
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities |  |
Amortized cost |  |
Within One Year | $ 3,537 |
After One Year through Five Years | 46,592 |
After Five Years through Ten Years | 133,018 |
After Ten Years | 7,327,572 |
Amortized Cost | 7,510,719 |
Fair value |  |
Within One Year | 3,494 |
After One Year through Five Years | 45,121 |
After Five Years through Ten Years | 124,704 |
After Ten Years | 7,139,482 |
Total | $ 7,312,801 |
Weighted Average Yield |  |
Within One Year | 2.72% |
After One Year through Five Years | 2.91% |
After Five Years through Ten Years | 2.80% |
After Ten Years | 5.49% |
Total | 5.42% |
Municipal securities |  |
Amortized cost |  |
Within One Year | $ 3,140 |
After One Year through Five Years | 32,928 |
After Five Years through Ten Years | 8,116 |
After Ten Years | 247,857 |
Amortized Cost | 292,041 |
Fair value |  |
Within One Year | 3,077 |
After One Year through Five Years | 31,538 |
After Five Years through Ten Years | 7,728 |
After Ten Years | 217,955 |
Total | $ 260,298 |
Weighted Average Yield |  |
Within One Year | 0.88% |
After One Year through Five Years | 2.37% |
After Five Years through Ten Years | 3.38% |
After Ten Years | 2.23% |
Total | 2.26% |
Non-agency mortgage-backed securities |  |
Amortized cost |  |
Within One Year | $ 74,825 |
After One Year through Five Years | 16,834 |
After Five Years through Ten Years | 9,347 |
After Ten Years | 795,853 |
Amortized Cost | 896,859 |
Fair value |  |
Within One Year | 74,153 |
After One Year through Five Years | 16,669 |
After Five Years through Ten Years | 9,304 |
After Ten Years | 695,714 |
Total | $ 795,840 |
Weighted Average Yield |  |
Within One Year | 4.44% |
After One Year through Five Years | 3.60% |
After Five Years through Ten Years | 6.04% |
After Ten Years | 2.46% |
Total | 2.68% |
Corporate debt securities |  |
Amortized cost |  |
Within One Year | $ 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 349,501 |
After Ten Years | 304,000 |
Amortized Cost | 653,501 |
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 307,110 |
After Ten Years | 224,709 |
Total | $ 531,819 |
Weighted Average Yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 0.00% |
After Five Years through Ten Years | 3.50% |
After Ten Years | 1.97% |
Total | 2.79% |
Foreign government bonds |  |
Amortized cost |  |
Within One Year | $ 26,238 |
After One Year through Five Years | 121,669 |
After Five Years through Ten Years | 50,000 |
After Ten Years | 50,000 |
Amortized Cost | 247,907 |
Fair value |  |
Within One Year | 26,303 |
After One Year through Five Years | 123,275 |
After Five Years through Ten Years | 49,744 |
After Ten Years | 39,547 |
Total | $ 238,869 |
Weighted Average Yield |  |
Within One Year | 3.23% |
After One Year through Five Years | 2.22% |
After Five Years through Ten Years | 5.74% |
After Ten Years | 1.50% |
Total | 2.90% |
Asset-backed securities |  |
Amortized cost |  |
Within One Year | $ 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 0 |
After Ten Years | 36,195 |
Amortized Cost | 36,195 |
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 0 |
After Ten Years | 35,735 |
Total | $ 35,735 |
Weighted Average Yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 0.00% |
After Five Years through Ten Years | 0.00% |
After Ten Years | 6.01% |
Total | 6.01% |
Collateralized loan obligations (“CLOs”) |  |
Amortized cost |  |
Within One Year | $ 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 44,500 |
After Ten Years | 0 |
Amortized Cost | 44,500 |
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 44,494 |
After Ten Years | 0 |
Total | $ 44,494 |
Weighted Average Yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 0.00% |
After Five Years through Ten Years | 6.74% |
After Ten Years | 0.00% |
Total | 6.74% |

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