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Investment Securities - Schedule of Amortized Cost and Fair Value by Contractual Maturity of Investment Securities HTM and AFS (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Investment securities HTM, Fair value |  |
Fair value | $ 2,476,289 | $ 2,524,525
Investment securities AFS, Amortized cost |  |
Amortized Cost | 8,142,396 | 8,079,918
Investment securities AFS, Fair value |  |
Fair value | 7,798,824 | 7,551,018
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Investment securities HTM, Amortized cost |  |
Within One Year | 0 |
1 to 5 Years | 0 |
5 to 10 Years | 0 |
More Than 10 Years | 2,502,639 |
Amortized cost | 2,502,639 |
Investment securities HTM, Fair value |  |
Within One Year | 0 |
1 to 5 Years | 0 |
5 to 10 Years | 0 |
More Than 10 Years | 2,476,289 |
Fair value | 2,476,289 | 2,524,525
Investment securities AFS, Amortized cost |  |
Within One Year | 0 |
1 to 5 Years | 0 |
5 to 10 Years | 0 |
More Than 10 Years | 2,239,222 |
Amortized Cost | 2,239,222 | 2,294,700
Investment securities AFS, Fair value |  |
Within One Year | 0 |
1 to 5 Years | 0 |
5 to 10 Years | 0 |
More Than 10 Years | 2,041,389 |
Fair value | 2,041,389 | 2,034,035
U.S. Treasury securities |  |
Investment securities AFS, Amortized cost |  |
Within One Year | 131,387 |
1 to 5 Years | 887,761 |
5 to 10 Years | 201,661 |
More Than 10 Years | 0 |
Amortized Cost | 1,220,809 | 1,214,363
Investment securities AFS, Fair value |  |
Within One Year | 131,900 |
1 to 5 Years | 902,835 |
5 to 10 Years | 206,191 |
More Than 10 Years | 0 |
Fair value | 1,240,926 | 1,212,742
U.S. Government agency securities |  |
Investment securities AFS, Amortized cost |  |
Within One Year | 0 |
1 to 5 Years | 29,995 |
5 to 10 Years | 0 |
More Than 10 Years | 0 |
Amortized Cost | 29,995 | 29,993
Investment securities AFS, Fair value |  |
Within One Year | 0 |
1 to 5 Years | 29,711 |
5 to 10 Years | 0 |
More Than 10 Years | 0 |
Fair value | 29,711 | 29,163
Mortgage-backed securities issued by U.S. Government agencies |  |
Investment securities AFS, Amortized cost |  |
Within One Year | 0 |
1 to 5 Years | 34 |
5 to 10 Years | 2 |
More Than 10 Years | 1,551,520 |
Amortized Cost | 1,551,556 | 1,583,331
Investment securities AFS, Fair value |  |
Within One Year | 0 |
1 to 5 Years | 34 |
5 to 10 Years | 2 |
More Than 10 Years | 1,456,852 |
Fair value | 1,456,888 | 1,462,790
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Investment securities AFS, Amortized cost |  |
Within One Year | 0 |
1 to 5 Years | 11 |
5 to 10 Years | 7,867 |
More Than 10 Years | 616,085 |
Amortized Cost | 623,963 | 657,453
Investment securities AFS, Fair value |  |
Within One Year | 0 |
1 to 5 Years | 11 |
5 to 10 Years | 7,718 |
More Than 10 Years | 527,940 |
Fair value | 535,669 | 550,201
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Investment securities AFS, Amortized cost |  |
Within One Year | 9,549 |
1 to 5 Years | 1,541,359 |
5 to 10 Years | 899,958 |
More Than 10 Years | 16,825 |
Amortized Cost | 2,467,691 | 2,290,968
Investment securities AFS, Fair value |  |
Within One Year | 9,436 |
1 to 5 Years | 1,550,689 |
5 to 10 Years | 910,364 |
More Than 10 Years | 14,585 |
Fair value | 2,485,074 | 2,253,116
Corporate debt securities and other debt securities |  |
Investment securities AFS, Amortized cost |  |
Within One Year | 0 |
1 to 5 Years | 9,160 |
5 to 10 Years | 0 |
More Than 10 Years | 0 |
Amortized Cost | 9,160 | 9,110
Investment securities AFS, Fair value |  |
Within One Year | 0 |
1 to 5 Years | 9,167 |
5 to 10 Years | 0 |
More Than 10 Years | 0 |
Fair value | $ 9,167 | $ 8,971

X
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