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INVESTMENT SECURITIES - Allowance for Credit Loss and Unrealized Losses and Fair Values (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Fair value |  |
Less than 12 Months, Fair value | $ 225,241 | $ 252,732
Less than 12 Months, Unrealized loss | 2,650 | 13,713
12 Months or more, Fair value | 534,325 | 460,879
12 Months or more, Unrealized loss | 80,578 | 86,201
Total, Fair value | 759,566 | 713,611
Total, Unrealized loss | 83,228 | 99,914
U.S. government sponsored entities and U.S. agency securities |  |
Fair value |  |
Less than 12 Months, Fair value | 12,266 | 42,826
Less than 12 Months, Unrealized loss | 43 | 87
12 Months or more, Fair value | 8,670 | 8,323
12 Months or more, Unrealized loss | 1,329 | 1,678
Total, Fair value | 20,936 | 51,149
Total, Unrealized loss | 1,372 | 1,765
Mortgage-backed securities - agency |  |
Fair value |  |
Less than 12 Months, Fair value | 136,270 | 130,106
Less than 12 Months, Unrealized loss | 690 | 7,386
12 Months or more, Fair value | 406,381 | 348,476
12 Months or more, Unrealized loss | 66,563 | 70,558
Total, Fair value | 542,651 | 478,582
Total, Unrealized loss | 67,253 | 77,944
Mortgage-backed securities - non-agency |  |
Fair value |  |
Less than 12 Months, Fair value | 6,580 | 8,852
Less than 12 Months, Unrealized loss | 66 | 353
12 Months or more, Fair value | 18,888 | 19,418
12 Months or more, Unrealized loss | 2,696 | 3,551
Total, Fair value | 25,468 | 28,270
Total, Unrealized loss | 2,762 | 3,904
State and municipal securities |  |
Fair value |  |
Less than 12 Months, Fair value | 1,802 | 51,497
Less than 12 Months, Unrealized loss | 26 | 5,750
12 Months or more, Fair value | 45,341 | 0
12 Months or more, Unrealized loss | 4,911 | 0
Total, Fair value | 47,143 | 51,497
Total, Unrealized loss | 4,937 | 5,750
Corporate securities |  |
Fair value |  |
Less than 12 Months, Fair value | 22,100 | 4,688
Less than 12 Months, Unrealized loss | 1,689 | 53
12 Months or more, Fair value | 55,045 | 84,662
12 Months or more, Unrealized loss | 5,079 | 10,414
Total, Fair value | 77,145 | 89,350
Total, Unrealized loss | 6,768 | 10,467
Other securities |  |
Fair value |  |
Less than 12 Months, Fair value | 46,223 | 14,763
Less than 12 Months, Unrealized loss | 136 | 84
12 Months or more, Fair value | 0 | 0
12 Months or more, Unrealized loss | 0 | 0
Total, Fair value | 46,223 | 14,763
Total, Unrealized loss | $ 136 | $ 84

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