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INVESTMENT SECURITIES - Unrealized Gain/Loss on Investment (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
AFS |  |
Amortized cost | $ 1,282,197 | $ 1,366,629
Gross unrealized gains | 366 | 834
Gross unrealized losses | (121,555) | (116,264)
Fair value | 1,161,008 | 1,251,199
Residential mortgage-backed securities |  |
AFS |  |
Amortized cost | 189,366 | 194,141
Gross unrealized gains | 106 | 117
Gross unrealized losses | (10,881) | (10,460)
Fair value | 178,591 | 183,798
Commercial mortgage-backed securities |  |
AFS |  |
Amortized cost | 55,083 | 55,235
Gross unrealized gains | 0 | 0
Gross unrealized losses | (7,613) | (7,479)
Fair value | 47,470 | 47,756
Residential collateralized mortgage obligations |  |
AFS |  |
Amortized cost | 407,152 | 473,269
Gross unrealized gains | 24 | 8
Gross unrealized losses | (35,516) | (33,539)
Fair value | 371,660 | 439,738
Commercial collateralized mortgage obligations |  |
AFS |  |
Amortized cost | 62,702 | 63,456
Gross unrealized gains | 0 | 0
Gross unrealized losses | (6,000) | (6,059)
Fair value | 56,702 | 57,397
Municipal bonds |  |
AFS |  |
Amortized cost | 449,327 | 452,057
Gross unrealized gains | 231 | 670
Gross unrealized losses | (51,458) | (47,853)
Fair value | 398,100 | 404,874
HTM |  |
Amortized cost | 2,354 | 2,371
Gross unrealized gains | 0 | 0
Gross unrealized losses | (49) | (40)
Fair value | 2,305 | 2,331
Corporate debt securities |  |
AFS |  |
Amortized cost | 41,159 | 45,611
Gross unrealized gains | 5 | 34
Gross unrealized losses | (6,012) | (7,098)
Fair value | 35,152 | 38,547
U.S. Treasury securities |  |
AFS |  |
Amortized cost | 22,571 | 22,658
Gross unrealized gains | 0 | 0
Gross unrealized losses | (2,675) | (2,474)
Fair value | 19,896 | 20,184
Agency debentures |  |
AFS |  |
Amortized cost | 54,837 | 60,202
Gross unrealized gains | 0 | 5
Gross unrealized losses | (1,400) | (1,302)
Fair value | $ 53,437 | $ 58,905

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