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Investment Securities - Amortized Cost and Fair Value - Held-to-maturity Securities (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | $ 91,172 | $ 92,009
Gross unrealized (losses) | (13,716) | (15,739)
Securities held-to-maturity, fair value | 77,456 | 76,270
U.S. Treasuries |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 6,002 | 6,001
Gross unrealized (losses) | (480) | (583)
Securities held-to-maturity, fair value | 5,522 | 5,418
U.S. government and federal agencies |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 35,341 | 35,349
Gross unrealized (losses) | (4,003) | (4,743)
Securities held-to-maturity, fair value | 31,338 | 30,606
U.S. agency collateralized mortgage obligations |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 17,430 | 17,805
Gross unrealized (losses) | (3,594) | (3,948)
Securities held-to-maturity, fair value | 13,836 | 13,857
Taxable municipal |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 6,037 | 6,041
Gross unrealized (losses) | (947) | (1,089)
Securities held-to-maturity, fair value | 5,090 | 4,952
U.S. agency mortgage-backed |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 26,362 | 26,813
Gross unrealized (losses) | (4,692) | (5,376)
Securities held-to-maturity, fair value | $ 21,670 | $ 21,437

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