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Investment Securities - Amortized Cost and Fair Value - Held-to-maturity Securities (Details) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | $ 92,863 | $ 95,505
Gross unrealized (losses) | (13,132) | (15,973)
Securities held-to-maturity, fair value | 79,731 | 79,532
U.S. Treasuries |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 6,002 | 6,001
Gross unrealized (losses) | (501) | (667)
Securities held-to-maturity, fair value | 5,501 | 5,334
U.S. government and federal agencies |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 35,359 | 35,434
Gross unrealized (losses) | (3,874) | (5,100)
Securities held-to-maturity, fair value | 31,485 | 30,334
U.S. agency collateralized mortgage obligations |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 18,227 | 19,395
Gross unrealized (losses) | (3,511) | (4,095)
Securities held-to-maturity, fair value | 14,716 | 15,300
Taxable municipal |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 6,045 | 6,057
Gross unrealized (losses) | (887) | (1,101)
Securities held-to-maturity, fair value | 5,158 | 4,956
U.S. agency mortgage-backed |  |
Securities Held-to-Maturity |  |
Amortized cost, held to maturity | 27,230 | 28,618
Gross unrealized (losses) | (4,359) | (5,010)
Securities held-to-maturity, fair value | $ 22,871 | $ 23,608

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