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Securities - Scheduled Contractual Maturities of AFS (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Amortized cost |  |
Within One Year | $ 583,428 |
After One Year through Five Years | 1,048,858 |
After Five Years through Ten Years | 986,581 |
After Ten Years | 4,357,464 |
Amortized Cost | 6,976,331 | $ 6,879,225
Fair value |  |
Within One Year | 581,600 |
After One Year through Five Years | 964,501 |
After Five Years through Ten Years | 874,214 |
After Ten Years | 3,619,522 |
Total | $ 6,039,837 |
Weighted Average Yield |  |
Within One Year | 5.32% |
After One Year through Five Years | 1.86% |
After Five Years through Ten Years | 4.27% |
After Ten Years | 3.40% |
Total | 3.45% |
U.S. Treasury securities |  |
Amortized cost |  |
Within One Year | $ 298,323 |
After One Year through Five Years | 676,292 |
After Five Years through Ten Years | 0 |
After Ten Years | 0 |
Amortized Cost | 974,615 |
Fair value |  |
Within One Year | 298,371 |
After One Year through Five Years | 605,730 |
After Five Years through Ten Years | 0 |
After Ten Years | 0 |
Total | $ 904,101 |
Weighted Average Yield |  |
Within One Year | 5.44% |
After One Year through Five Years | 1.20% |
After Five Years through Ten Years | 0.00% |
After Ten Years | 0.00% |
Total | 2.50% |
U.S. government-sponsored enterprises debt securities |  |
Amortized cost |  |
Within One Year | $ 150,000 |
After One Year through Five Years | 96,472 |
After Five Years through Ten Years | 103,171 |
After Ten Years | 163,069 |
Amortized Cost | 512,712 |
Fair value |  |
Within One Year | 149,616 |
After One Year through Five Years | 91,343 |
After Five Years through Ten Years | 82,252 |
After Ten Years | 124,253 |
Total | $ 447,464 |
Weighted Average Yield |  |
Within One Year | 4.98% |
After One Year through Five Years | 3.08% |
After Five Years through Ten Years | 1.39% |
After Ten Years | 2.18% |
Total | 3.01% |
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities |  |
Amortized cost |  |
Within One Year | $ 0 |
After One Year through Five Years | 42,260 |
After Five Years through Ten Years | 144,846 |
After Ten Years | 2,341,264 |
Amortized Cost | 2,528,370 |
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 39,718 |
After Five Years through Ten Years | 128,933 |
After Ten Years | 1,988,023 |
Total | $ 2,156,674 |
Weighted Average Yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 3.16% |
After Five Years through Ten Years | 2.73% |
After Ten Years | 3.68% |
Total | 3.62% |
Municipal securities |  |
Amortized cost |  |
Within One Year | $ 2,400 |
After One Year through Five Years | 36,850 |
After Five Years through Ten Years | 9,007 |
After Ten Years | 253,151 |
Amortized Cost | 301,408 |
Fair value |  |
Within One Year | 2,383 |
After One Year through Five Years | 33,794 |
After Five Years through Ten Years | 7,596 |
After Ten Years | 199,783 |
Total | $ 243,556 |
Weighted Average Yield |  |
Within One Year | 3.13% |
After One Year through Five Years | 2.34% |
After Five Years through Ten Years | 2.87% |
After Ten Years | 2.24% |
Total | 2.28% |
Non-agency mortgage-backed securities |  |
Amortized cost |  |
Within One Year | $ 99,830 |
After One Year through Five Years | 92,328 |
After Five Years through Ten Years | 11,056 |
After Ten Years | 902,911 |
Amortized Cost | 1,106,125 |
Fair value |  |
Within One Year | 98,420 |
After One Year through Five Years | 89,370 |
After Five Years through Ten Years | 10,793 |
After Ten Years | 737,524 |
Total | $ 936,107 |
Weighted Average Yield |  |
Within One Year | 6.27% |
After One Year through Five Years | 4.16% |
After Five Years through Ten Years | 0.80% |
After Ten Years | 2.58% |
Total | 3.02% |
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 | 280,812 |
After Ten Years | 194,622 |
Total | $ 475,434 |
Weighted Average Yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 0.00% |
After Five Years through Ten Years | 3.48% |
After Ten Years | 1.97% |
Total | 2.78% |
Foreign government bonds |  |
Amortized cost |  |
Within One Year | $ 32,875 |
After One Year through Five Years | 104,656 |
After Five Years through Ten Years | 50,000 |
After Ten Years | 50,000 |
Amortized Cost | 237,531 |
Fair value |  |
Within One Year | 32,810 |
After One Year through Five Years | 104,546 |
After Five Years through Ten Years | 49,609 |
After Ten Years | 35,825 |
Total | $ 222,790 |
Weighted Average Yield |  |
Within One Year | 3.02% |
After One Year through Five Years | 2.28% |
After Five Years through Ten Years | 5.71% |
After Ten Years | 1.50% |
Total | 2.94% |
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 | 44,819 |
Amortized Cost | 44,819 |
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 0 |
After Ten Years | 43,757 |
Total | $ 43,757 |
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 | 319,000 |
After Ten Years | 298,250 |
Amortized Cost | 617,250 |
Fair value |  |
Within One Year | 0 |
After One Year through Five Years | 0 |
After Five Years through Ten Years | 314,219 |
After Ten Years | 295,735 |
Total | $ 609,954 |
Weighted Average Yield |  |
Within One Year | 0.00% |
After One Year through Five Years | 0.00% |
After Five Years through Ten Years | 6.71% |
After Ten Years | 6.76% |
Total | 6.73% |

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