Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Financial Assets
Securities available for sale	$ 481,509	$ 432,233
Equity securities	8,307	7,909
Loan yield maintenance provisions	4,747	1,898
Fair Value, Measurements, Recurring
Financial Assets
Total investment securities	489,816	440,142
Loan yield maintenance provisions	4,747	1,898
Corporate bonds
Financial Assets
Securities available for sale	3,721	1,260
Corporate bonds \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	3,721	1,260
Collateralized mortgage obligations \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	29,559	11,347
Small Business Administration
Financial Assets
Securities available for sale	5,838	6,480
Small Business Administration \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	5,838	6,480
Other investments measured at net asset value \| Fair Value, Measurements, Recurring
Financial Assets
Equity securities	7,877	7,315
U.S. Treasury and U.S. government sponsored entities
Financial Assets
Securities available for sale	3,908	3,811
U.S. Treasury and U.S. government sponsored entities \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	3,908	3,811
State and political subdivisions
Financial Assets
Securities available for sale	327,421	261,425
State and political subdivisions \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	327,421	261,425
Mortgage-backed securities - residential
Financial Assets
Securities available for sale	111,062	147,910
Mortgage-backed securities - residential \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	111,062	147,910
Equity securities at fair value \| Fair Value, Measurements, Recurring
Financial Assets
Equity securities	430	594
Interest rate swaps \| Fair Value, Measurements, Recurring
Financial Liabilities
Derivative liabilities	4,747	1,898
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Fair Value, Measurements, Recurring
Financial Assets
Total investment securities	430	594
Loan yield maintenance provisions	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate bonds \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Collateralized mortgage obligations \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Small Business Administration \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury and U.S. government sponsored entities \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| State and political subdivisions \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed securities - residential \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Equity securities at fair value \| Fair Value, Measurements, Recurring
Financial Assets
Equity securities	430	594
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Interest rate swaps \| Fair Value, Measurements, Recurring
Financial Liabilities
Derivative liabilities	0	0
Significant Other Observable Inputs (Level 2) \| Fair Value, Measurements, Recurring
Financial Assets
Total investment securities	481,505	432,228
Loan yield maintenance provisions	4,747	1,898
Significant Other Observable Inputs (Level 2) \| Corporate bonds \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	3,721	1,260
Significant Other Observable Inputs (Level 2) \| Collateralized mortgage obligations \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	29,559	11,347
Significant Other Observable Inputs (Level 2) \| Small Business Administration \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	5,838	6,480
Significant Other Observable Inputs (Level 2) \| U.S. Treasury and U.S. government sponsored entities \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	3,908	3,811
Significant Other Observable Inputs (Level 2) \| State and political subdivisions \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	327,421	261,425
Significant Other Observable Inputs (Level 2) \| Mortgage-backed securities - residential \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	111,058	147,905
Significant Other Observable Inputs (Level 2) \| Equity securities at fair value \| Fair Value, Measurements, Recurring
Financial Assets
Equity securities	0	0
Significant Other Observable Inputs (Level 2) \| Interest rate swaps \| Fair Value, Measurements, Recurring
Financial Liabilities
Derivative liabilities	4,747	1,898
Significant Unobservable Inputs (Level 3) \| Fair Value, Measurements, Recurring
Financial Assets
Total investment securities	4	5
Loan yield maintenance provisions	0	0
Significant Unobservable Inputs (Level 3) \| Corporate bonds \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Collateralized mortgage obligations \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Small Business Administration \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| U.S. Treasury and U.S. government sponsored entities \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| State and political subdivisions \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	0	0
Significant Unobservable Inputs (Level 3) \| Mortgage-backed securities - residential \| Fair Value, Measurements, Recurring
Financial Assets
Securities available for sale	4	5
Significant Unobservable Inputs (Level 3) \| Equity securities at fair value \| Fair Value, Measurements, Recurring
Financial Assets
Equity securities	0	0
Significant Unobservable Inputs (Level 3) \| Interest rate swaps \| Fair Value, Measurements, Recurring
Financial Liabilities
Derivative liabilities	$ 0	$ 0

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