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Fair Value of Assets and Liabilities - Recorded on a Recurring Basis (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | $ 963,033 | $ 392,351
SBA-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 34,609 | 32,862
Debentures of government- sponsored agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 70,214 | 20,186
U.S. Treasury securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 11,777 |
Obligations of state and political subdivisions |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 137,215 | 110,652
Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 13,777 |
Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 1,909 |
Carrying Value | Assets and liabilities at fair value measured on a recurring basis |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial liabilities (interest rate contracts) | 1,266 | 1,912
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government-sponsored agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 693,532 | 228,651
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | SBA-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 34,609 | 32,862
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | Debentures of government- sponsored agencies |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 70,214 | 20,186
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | U.S. Treasury securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 11,777 |
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | Obligations of state and political subdivisions |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 137,215 | 110,652
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | Corporate bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 13,777 |
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | Asset-backed securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 1,909 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial liabilities (interest rate contracts) | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial liabilities (interest rate contracts) | 1,266 | 1,912
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Derivative financial liabilities (interest rate contracts) | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government-sponsored agencies | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government-sponsored agencies | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 693,532 | 228,651
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Mortgage-backed securities and collateralized mortgage obligations issued by U.S. government-sponsored agencies | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | SBA-backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | SBA-backed securities | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 34,609 | 36,286
Fair Value | Assets and liabilities at fair value measured on a recurring basis | SBA-backed securities | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Debentures of government- sponsored agencies | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Debentures of government- sponsored agencies | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 70,214 | 20,186
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Debentures of government- sponsored agencies | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | U.S. Treasury securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 11,777 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | U.S. Treasury securities | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | U.S. Treasury securities | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Obligations of state and political subdivisions | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Obligations of state and political subdivisions | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 137,215 | 110,652
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Obligations of state and political subdivisions | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 | $ 0
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Corporate bonds | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Corporate bonds | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 13,777 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Corporate bonds | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Asset-backed securities | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 0 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Asset-backed securities | Significant Other Observable Inputs (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | 1,909 |
Fair Value | Assets and liabilities at fair value measured on a recurring basis | Asset-backed securities | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Available-for-sale securities | $ 0 |

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