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Securities - Scheduled Contractual Maturities of AFS (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Amortized cost |  |
Within One Year | $ 511,271 |
After One Year through Five Years | 653,228 |
After Five Years through Ten Years | 818,657 |
After Ten Years | 11,206,157 |
Total | 13,189,313 | $ 11,505,775
Fair value |  |
Within One Year | 507,629 |
After One Year through Five Years | 633,745 |
After Five Years through Ten Years | 729,367 |
After Ten Years | 10,870,411 |
Total | $ 12,741,152 |
Weighted-average yield |  |
Within One Year | 2.73% |
After One Year through Five Years | 1.61% |
After Five Years through Ten Years | 2.77% |
After Ten Years | 4.79% |
Total | 4.42% |
U.S. Treasury securities |  |
Amortized cost |  |
Within One Year | $ 339,871 |
After One Year through Five Years | 486,357 |
After Five Years through Ten Years | 49,349 |
After Ten Years | 0 |
Total | 875,577 | 676,300
Fair value |  |
Within One Year | 336,058 |
After One Year through Five Years | 470,466 |
After Five Years through Ten Years | 49,691 |
After Ten Years | 0 |
Total | $ 856,215 |
Weighted-average yield |  |
Within One Year | 2.61% |
After One Year through Five Years | 1.32% |
After Five Years through Ten Years | 3.95% |
After Ten Years | 0.00% |
Total | 1.97% |
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Amortized cost |  |
Within One Year | $ 0 |
After One Year through Five Years | 26,677 |
After Five Years through Ten Years | 200,833 |
After Ten Years | 60,858 |
Total | 288,368 | 308,220
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 26,066 |
After Five Years through Ten Years | 178,519 |
After Ten Years | 51,801 |
Total | $ 256,386 |
Weighted-average yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 1.58% |
After Five Years through Ten Years | 2.06% |
After Ten Years | 2.19% |
Total | 2.05% |
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities |  |
Amortized cost |  |
Within One Year | $ 4,755 |
After One Year through Five Years | 83,696 |
After Five Years through Ten Years | 111,891 |
After Ten Years | 9,975,959 |
Total | 10,176,301 |
Fair value |  |
Within One Year | 4,741 |
After One Year through Five Years | 81,229 |
After Five Years through Ten Years | 103,361 |
After Ten Years | 9,822,535 |
Total | $ 10,011,866 |
Weighted-average yield |  |
Within One Year | 3.57% |
After One Year through Five Years | 2.91% |
After Five Years through Ten Years | 2.94% |
After Ten Years | 5.10% |
Total | 5.05% |
Municipal securities |  |
Amortized cost |  |
Within One Year | $ 9,098 |
After One Year through Five Years | 21,298 |
After Five Years through Ten Years | 22,629 |
After Ten Years | 228,990 |
Total | 282,015 | 287,301
Fair value |  |
Within One Year | 8,987 |
After One Year through Five Years | 20,689 |
After Five Years through Ten Years | 19,446 |
After Ten Years | 196,060 |
Total | $ 245,182 |
Weighted-average yield |  |
Within One Year | 1.85% |
After One Year through Five Years | 2.41% |
After Five Years through Ten Years | 2.40% |
After Ten Years | 2.26% |
Total | 2.27% |
Non-agency mortgage-backed securities |  |
Amortized cost |  |
Within One Year | $ 3,970 |
After One Year through Five Years | 2,899 |
After Five Years through Ten Years | 1,955 |
After Ten Years | 682,701 |
Total | 691,525 |
Fair value |  |
Within One Year | 3,924 |
After One Year through Five Years | 2,875 |
After Five Years through Ten Years | 1,955 |
After Ten Years | 592,917 |
Total | $ 601,671 |
Weighted-average yield |  |
Within One Year | 5.21% |
After One Year through Five Years | 3.21% |
After Five Years through Ten Years | 5.34% |
After Ten Years | 2.28% |
Total | 2.30% |
Corporate debt securities |  |
Amortized cost |  |
Within One Year | $ 35,900 |
After One Year through Five Years | 4,000 |
After Five Years through Ten Years | 382,000 |
After Ten Years | 175,000 |
Total | 596,900 | 653,500
Fair value |  |
Within One Year | 35,785 |
After One Year through Five Years | 3,975 |
After Five Years through Ten Years | 326,549 |
After Ten Years | 134,561 |
Total | $ 500,870 |
Weighted-average yield |  |
Within One Year | 4.45% |
After One Year through Five Years | 4.00% |
After Five Years through Ten Years | 2.69% |
After Ten Years | 2.02% |
Total | 2.61% |
Foreign government bonds |  |
Amortized cost |  |
Within One Year | $ 117,677 |
After One Year through Five Years | 28,301 |
After Five Years through Ten Years | 50,000 |
After Ten Years | 50,000 |
Total | 245,978 | 244,803
Fair value |  |
Within One Year | 118,134 |
After One Year through Five Years | 28,445 |
After Five Years through Ten Years | 49,846 |
After Ten Years | 40,594 |
Total | $ 237,019 |
Weighted-average yield |  |
Within One Year | 2.49% |
After One Year through Five Years | 1.81% |
After Five Years through Ten Years | 4.74% |
After Ten Years | 1.50% |
Total | 2.67% |
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 | 32,649 |
Total | 32,649 | $ 35,086
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 0 |
After Ten Years | 31,943 |
Total | $ 31,943 |
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 | 5.04% |
Total | 5.04% |

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