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Investment Securities - Available-for-Sale Securities Amortized Cost and Fair Value (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | $ 373,038,000 | $ 423,923,000
Gross Unrealized Gains | 19,393,000 | 8,748,000
Gross Unrealized (Losses) | (80,000) | (411,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 392,351,000 | 432,260,000
Other assets |  |
Debt Securities, Available-for-sale [Line Items] |  |
Accrued interest | 1,900,000 | 1,800,000
MBS pass-through securities issued by FHLMC and FNMA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 50,686,000 | 98,502,000
Gross Unrealized Gains | 2,530,000 | 1,617,000
Gross Unrealized (Losses) | 0 | (48,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 53,216,000 | 100,071,000
CMOs issued by FHLMC |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 143,267,000 | 139,398,000
Gross Unrealized Gains | 7,925,000 | 3,892,000
Gross Unrealized (Losses) | (1,000) | (64,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 151,191,000 | 143,226,000
CMOs issued by FNMA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 16,450,000 | 22,702,000
Gross Unrealized Gains | 580,000 | 390,000
Gross Unrealized (Losses) | 0 | 0
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 17,030,000 | 23,092,000
CMOs issued by GNMA |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 6,863,000 | 11,719,000
Gross Unrealized Gains | 351,000 | 42,000
Gross Unrealized (Losses) | 0 | (6,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 7,214,000 | 11,755,000
SBA-backed securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 30,941,000 | 35,674,000
Gross Unrealized Gains | 1,976,000 | 688,000
Gross Unrealized (Losses) | (55,000) | (76,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 32,862,000 | 36,286,000
Debentures of government sponsored agencies |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 19,944,000 | 48,389,000
Gross Unrealized Gains | 266,000 | 727,000
Gross Unrealized (Losses) | (24,000) | (70,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | 20,186,000 | 49,046,000
Obligations of state and political subdivisions |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost | 104,887,000 | 66,042,000
Gross Unrealized Gains | 5,765,000 | 1,386,000
Gross Unrealized (Losses) | 0 | (146,000)
Allowance for Credit Losses | 0 | 0
Securities available for sale, Fair Value | $ 110,652,000 | 67,282,000
Corporate bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Amortized Cost |  | 1,497,000
Gross Unrealized Gains |  | 6,000
Gross Unrealized (Losses) |  | (1,000)
Allowance for Credit Losses |  | 0
Securities available for sale, Fair Value |  | $ 1,502,000

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