Loans - Delinquent Loans (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2020 USD ($) payment	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	$ 12,051	$ 12,355
Current Loans	649,431	585,019
Total Loans	661,482	597,374	$ 570,128
Accruing Loans 90 or More Days Past Due	$ 53	386
Minimum period of default	90 days
Number of monthly payments to demonstrate repayment ability | payment	6
Undisbursed commitments	$ 0	0
Total nonaccrual Loans	11,535	11,697
Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	643
Current Loans	65,742	44,635
Total Loans	65,742	45,278	48,137
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	75
Commercial and Industrial | Commercial and business loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	643
Current Loans	39,218	43,891
Total Loans	39,218	44,534	47,355
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	75
Commercial and Industrial | Government program loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Current Loans	26,524	744
Total Loans	26,524	744	782
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	0
Real estate mortgage
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	266	28
Current Loans	309,583	291,209
Total Loans	309,849	291,237	275,959
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	0
Real estate mortgage | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Current Loans	264,013	245,183
Total Loans	264,013	245,183	224,713
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	0
Real estate mortgage | Residential mortgages
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	266	28
Current Loans	45,456	45,853
Total Loans	45,722	45,881	51,062
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	0
Real estate mortgage | Home improvement and home equity loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Current Loans	114	173
Total Loans	114	173	184
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	0	0
Real estate construction and development
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	8,573	8,825
Current Loans	163,316	129,959
Total Loans	171,889	138,784	116,443
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	11,058	11,478
Agricultural loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	477	1,524
Current Loans	51,110	50,673
Total Loans	51,587	52,197	60,100
Accruing Loans 90 or More Days Past Due	0	0
Total nonaccrual Loans	477	144
Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	2,735	1,335
Current Loans	59,680	68,543
Total Loans	62,415	69,878	$ 69,489
Accruing Loans 90 or More Days Past Due	53	386
Total nonaccrual Loans	0	0
Installment and student loans | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	2,735	1,335
Current Loans	59,580	68,280
Total Loans	62,315	69,615
Accruing Loans 90 or More Days Past Due	53	386
Installment and student loans | Overdraft protection lines
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Current Loans	30	33
Total Loans	30	33
Accruing Loans 90 or More Days Past Due	0	0
Installment and student loans | Overdrafts
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Current Loans	70	230
Total Loans	70	230
Accruing Loans 90 or More Days Past Due	0	0
Loans 30-60 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	2,519	1,845
Loans 30-60 Days Past Due | Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	568
Loans 30-60 Days Past Due | Commercial and Industrial | Commercial and business loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	568
Loans 30-60 Days Past Due | Commercial and Industrial | Government program loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 30-60 Days Past Due | Real estate mortgage
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	266	28
Loans 30-60 Days Past Due | Real estate mortgage | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 30-60 Days Past Due | Real estate mortgage | Residential mortgages
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	266	28
Loans 30-60 Days Past Due | Real estate mortgage | Home improvement and home equity loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 30-60 Days Past Due | Real estate construction and development
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 30-60 Days Past Due | Agricultural loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	957
Loans 30-60 Days Past Due | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	2,253	292
Loans 30-60 Days Past Due | Installment and student loans | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	2,253	292
Loans 30-60 Days Past Due | Installment and student loans | Overdraft protection lines
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 30-60 Days Past Due | Installment and student loans | Overdrafts
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	429	1,080
Loans 61-89 Days Past Due | Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Commercial and Industrial | Commercial and business loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Commercial and Industrial | Government program loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Real estate mortgage
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Real estate mortgage | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Real estate mortgage | Residential mortgages
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Real estate mortgage | Home improvement and home equity loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Real estate construction and development
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Agricultural loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	423
Loans 61-89 Days Past Due | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	429	657
Loans 61-89 Days Past Due | Installment and student loans | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	429	657
Loans 61-89 Days Past Due | Installment and student loans | Overdraft protection lines
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 61-89 Days Past Due | Installment and student loans | Overdrafts
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	9,103	9,430
Loans 90 or More Days Past Due | Commercial and Industrial
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	75
Loans 90 or More Days Past Due | Commercial and Industrial | Commercial and business loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	75
Loans 90 or More Days Past Due | Commercial and Industrial | Government program loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due | Real estate mortgage
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due | Real estate mortgage | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due | Real estate mortgage | Residential mortgages
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due | Real estate mortgage | Home improvement and home equity loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due | Real estate construction and development
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	8,573	8,825
Loans 90 or More Days Past Due | Agricultural loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	477	144
Loans 90 or More Days Past Due | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	53	386
Loans 90 or More Days Past Due | Installment and student loans | Installment and student loans
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	53	386
Loans 90 or More Days Past Due | Installment and student loans | Overdraft protection lines
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	0	0
Loans 90 or More Days Past Due | Installment and student loans | Overdrafts
Financing Receivable, Past Due [Line Items]
Total Past Due Loans	$ 0	$ 0