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Securities - Schedule of Information Regarding Securities with Unrealized Losses (Details) - USD ($) $ in Thousands | Jun. 30, 2025 | Dec. 31, 2024
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Securities in an Unrealized Loss Position for Less than Twelve Months |  |
Fair value, AFS and HTM | $ 281,705 | $ 442,489
Unrealized losses, AFS and HTM | 1,343 | 2,441
Securities in an Unrealized Loss Position for More than Twelve Months |  |
Fair value, AFS and HTM | 1,968,439 | 1,975,663
Unrealized losses, AFS and HTM | 387,127 | 457,102
Total |  |
Fair value, AFS and HTM | 2,250,144 | 2,418,152
Unrealized losses, AFS and HTM | 388,470 | 459,543
U.S. Treasuries |  |
Securities in an Unrealized Loss Position for Less than Twelve Months |  |
Fair value, AFS |  | 120,581
Unrealized losses, AFS |  | 470
Securities in an Unrealized Loss Position for More than Twelve Months |  |
Fair value, AFS |  | 0
Unrealized losses, AFS |  | 0
Total |  |
Fair value, AFS |  | 120,581
Unrealized losses, AFS |  | 470
Government-sponsored enterprise securities |  |
Securities in an Unrealized Loss Position for Less than Twelve Months |  |
Fair value, AFS | 0 | 0
Unrealized losses, AFS | 0 | 0
Securities in an Unrealized Loss Position for More than Twelve Months |  |
Fair value, AFS | 10,097 | 9,614
Unrealized losses, AFS | 1,867 | 2,347
Total |  |
Fair value, AFS | 10,097 | 9,614
Unrealized losses, AFS | 1,867 | 2,347
Mortgage-backed securities |  |
Securities in an Unrealized Loss Position for Less than Twelve Months |  |
Fair value, AFS and HTM | 277,088 | 317,015
Unrealized losses, AFS and HTM | 1,302 | 1,845
Securities in an Unrealized Loss Position for More than Twelve Months |  |
Fair value, AFS and HTM | 1,536,577 | 1,538,156
Unrealized losses, AFS and HTM | 300,486 | 363,423
Total |  |
Fair value, AFS and HTM | 1,813,665 | 1,855,171
Unrealized losses, AFS and HTM | 301,788 | 365,268
Corporate bonds |  |
Securities in an Unrealized Loss Position for Less than Twelve Months |  |
Fair value, AFS | 0 | 380
Unrealized losses, AFS | 0 | 51
Securities in an Unrealized Loss Position for More than Twelve Months |  |
Fair value, AFS | 3,324 | 13,562
Unrealized losses, AFS | 113 | 438
Total |  |
Fair value, AFS | 3,324 | 13,942
Unrealized losses, AFS | 113 | 489
State and local governments |  |
Securities in an Unrealized Loss Position for Less than Twelve Months |  |
Fair value, AFS and HTM | 4,617 | 4,513
Unrealized losses, AFS and HTM | 41 | 75
Securities in an Unrealized Loss Position for More than Twelve Months |  |
Fair value, AFS and HTM | 418,441 | 414,331
Unrealized losses, AFS and HTM | 84,661 | 90,894
Total |  |
Fair value, AFS and HTM | 423,058 | 418,844
Unrealized losses, AFS and HTM | $ 84,702 | $ 90,969

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