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Fair Value of Assets and Liabilities - Recorded on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 518,568	$ 392,351
SBA-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	29,218	32,862
Debentures of government- sponsored agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	74,473	20,186
Obligations of state and political subdivisions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	121,765	110,652
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	5,789
Assets and liabilities at fair value measured on a recurring basis | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial liabilities (interest rate contracts)	0	0
Assets and liabilities at fair value measured on a recurring basis | Significant Other Observable Inputs (Level 2) | Interest rate contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial liabilities (interest rate contracts)	1,193	1,912
Assets and liabilities at fair value measured on a recurring basis | Significant Unobservable Inputs  (Level 3) | Interest rate contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial liabilities (interest rate contracts)	0	0
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
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	287,323	228,651
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
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
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	29,218	36,286
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
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
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	74,473	20,186
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
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
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	121,765	110,652
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
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
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	5,789
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
Carrying Value | Assets and liabilities at fair value measured on a recurring basis | Interest rate contract
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative financial liabilities (interest rate contracts)	1,193	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	287,323	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	29,218	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	74,473	20,186
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	121,765	$ 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	$ 5,789

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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