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Investment Securities (Details) - USD ($) | Apr. 01, 2021 | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | --- | ---
Investment securities available-for-sale |  |  |
Amortized Cost |  | $ 584,754,000 | $ 849,567,000
Unrealized Gains |  | 5,000 | 21,000
Unrealized Losses |  | (98,023,000) | (132,264,000)
Allowance for Credit Losses |  | 0 | 0
Fair Value |  | 486,736,000 | 717,324,000
Amortized Cost |  | 299,728,000 | 321,902,000
Unrealized Losses |  | (41,111,000) | (50,990,000)
Allowance for Credit Losses |  | 213,000 | 0
Fair Value |  | 258,617,000 | 270,912,000
Amortized Cost |  | 884,482,000 | 1,171,469,000
Unrealized Gains |  | 5,000 | 21,000
Unrealized Losses |  | (139,134,000) | (183,254,000)
Allowance for Credit Losses |  | 213,000 |
Fair Value |  | 745,353,000 | 988,236,000
Available-for-Sale accrued interest receivable |  | $ 1,500,000 | $ 1,900,000
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] |  | Fair Value | Fair Value
Held-to-Maturity accrued interest receivable |  | $ 1,400,000 | $ 1,500,000
Debt Securities, Held-to-Maturity, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] |  | Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss | Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss
Net unrealized gains on the transferred securities |  | $ 108,000 | $ 272,000
Deferred tax on the transferred securities |  | 55,000 | 137,000
U.S. treasury and government agencies |  |  |
Investment securities available-for-sale |  |  |
Amortized Cost |  | 1,119,000 | 3,518,000
Unrealized Gains |  | 4,000 | 19,000
Unrealized Losses |  | (3,000) | (17,000)
Fair Value |  | 1,120,000 | 3,520,000
Mortgage backed securities - Residential agency |  |  |
Investment securities available-for-sale |  |  |
Amortized Cost |  | 524,140,000 | 705,845,000
Unrealized Gains |  | 1,000 | 2,000
Unrealized Losses |  | (88,547,000) | (118,168,000)
Fair Value |  | 435,594,000 | 587,679,000
Amortized Cost |  | 170,125,000 | 184,115,000
Unrealized Losses |  | (28,498,000) | (33,254,000)
Allowance for Credit Losses |  | 99,000 |
Fair Value |  | 141,627,000 | 150,861,000
Mortgage backed securities - Commercial |  |  |
Investment securities available-for-sale |  |  |
Amortized Cost |  | 1,476,000 | 70,669,000
Unrealized Losses |  | (123,000) | (7,111,000)
Fair Value |  | 1,353,000 | 63,558,000
Asset backed securities |  |  |
Investment securities available-for-sale |  |  |
Amortized Cost |  | 26,000 | 34,000
Unrealized Losses |  | (1,000) |
Fair Value |  | 25,000 | 34,000
Corporate bonds |  |  |
Investment securities available-for-sale |  |  |
Amortized Cost |  | 57,993,000 | 69,501,000
Unrealized Losses |  | (9,349,000) | (6,968,000)
Fair Value |  | 48,644,000 | 62,533,000
Obligations of state and political agencies. |  |  |
Investment securities available-for-sale |  |  |
Amortized Cost |  | 129,603,000 | 137,787,000
Unrealized Losses |  | (12,613,000) | (17,736,000)
Allowance for Credit Losses |  | 114,000 |
Fair Value |  | $ 116,990,000 | $ 120,051,000
Fair value of debt securities available-for-sale transferred to held-to-maturity | $ 149,200,000 |  |
Net unrealized gain from available-for-sale to held-to-maturity | $ 1,300,000 |  |

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