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INVESTMENT SECURITIES - Allowance for Credit Loss and Unrealized Losses and Fair Values (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | $ 122,446 | $ 388,077
Less than 12 Months, Unrealized loss | 1,290 | 12,176
12 Months or more, Fair value | 687,052 | 515,505
12 Months or more, Unrealized loss | 88,749 | 100,182
Total, Fair value | 809,498 | 903,582
Total, Unrealized loss | 90,039 | 112,358
U.S. government sponsored entities and U.S. agency securities |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 4,979 | 4,973
Less than 12 Months, Unrealized loss | 7 | 27
12 Months or more, Fair value | 8,979 | 8,488
12 Months or more, Unrealized loss | 1,022 | 1,512
Total, Fair value | 13,958 | 13,461
Total, Unrealized loss | 1,029 | 1,539
Mortgage-backed securities - agency |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 84,803 | 300,427
Less than 12 Months, Unrealized loss | 1,145 | 9,735
12 Months or more, Fair value | 539,599 | 385,332
12 Months or more, Unrealized loss | 77,432 | 85,133
Total, Fair value | 624,402 | 685,759
Total, Unrealized loss | 78,577 | 94,868
Mortgage-backed securities - non-agency |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 712 | 12,433
Less than 12 Months, Unrealized loss | 1 | 33
12 Months or more, Fair value | 22,787 | 24,153
12 Months or more, Unrealized loss | 2,569 | 3,416
Total, Fair value | 23,499 | 36,586
Total, Unrealized loss | 2,570 | 3,449
Asset-backed student loans |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 14,659 | 17,734
Less than 12 Months, Unrealized loss | 36 | 99
12 Months or more, Fair value | 15,263 | 2,130
12 Months or more, Unrealized loss | 93 | 1
Total, Fair value | 29,922 | 19,864
Total, Unrealized loss | 129 | 100
State and municipal securities |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 7,336 | 21,209
Less than 12 Months, Unrealized loss | 51 | 365
12 Months or more, Fair value | 46,740 | 43,131
12 Months or more, Unrealized loss | 4,522 | 6,267
Total, Fair value | 54,076 | 64,340
Total, Unrealized loss | 4,573 | 6,632
Collateralized loan obligations |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 9,957 | 7,468
Less than 12 Months, Unrealized loss | 50 | 7
12 Months or more, Fair value | 0 | 0
12 Months or more, Unrealized loss | 0 | 0
Total, Fair value | 9,957 | 7,468
Total, Unrealized loss | 50 | 7
Corporate securities |  |
Available For Sale Securities, Continuous Unrealized Loss Position, Fair Values |  |
Less than 12 Months, Fair value | 0 | 23,833
Less than 12 Months, Unrealized loss | 0 | 1,910
12 Months or more, Fair value | 53,684 | 52,271
12 Months or more, Unrealized loss | 3,111 | 3,853
Total, Fair value | 53,684 | 76,104
Total, Unrealized loss | $ 3,111 | $ 5,763

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