Loans - Credit Risk Rating for Commercial, Construction and Non-Consumer Related Loans (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2021 USD ($) rating	Dec. 31, 2020 USD ($)
Receivables [Abstract]
Number of risk rating approaches | rating	2
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	$ 832,849	$ 645,825
Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	56,084	47,514
Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	333,288	282,951
Commercial Real Estate | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	176,501	37,236
Commercial Real Estate | Home improvement and home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	96	107
Real Estate Construction and Development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	165,426	175,016
Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	53,518	51,079
Commercial, Construction and Other Non-Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	608,316	556,560
Installment and student loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	56,190	61,508
Real Estate and Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	232,787	98,851
Grades 1 and 2 | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	12,415	9,811
Grades 1 and 2 | Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Grades 1 and 2 | Real Estate Construction and Development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Grades 1 and 2 | Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	30
Grades 1 and 2 | Commercial, Construction and Other Non-Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	12,415	9,841
Grade 3 | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Grade 3 | Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	483	519
Grade 3 | Real Estate Construction and Development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Grade 3 | Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Grade 3 | Commercial, Construction and Other Non-Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	483	519
Grades 4 and 5 – pass | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	43,506	35,919
Grades 4 and 5 – pass | Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	310,404	267,215
Grades 4 and 5 – pass | Real Estate Construction and Development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	154,486	163,959
Grades 4 and 5 – pass | Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	40,335	49,006
Grades 4 and 5 – pass | Commercial, Construction and Other Non-Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	548,731	516,099
Grade 6 – special mention | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	1,307
Grade 6 – special mention | Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	22,401	14,343
Grade 6 – special mention | Real Estate Construction and Development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Grade 6 – special mention | Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	12,804	1,434
Grade 6 – special mention | Commercial, Construction and Other Non-Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	35,205	17,084
Grade 7 – substandard | Commercial and Industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	163	477
Grade 7 – substandard | Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	874
Grade 7 – substandard | Real Estate Construction and Development
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	10,940	11,057
Grade 7 – substandard | Agricultural
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	379	609
Grade 7 – substandard | Commercial, Construction and Other Non-Consumer Loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	11,482	13,017
Not graded | Commercial Real Estate | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	166,012	27,484
Not graded | Commercial Real Estate | Home improvement and home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	82	92
Not graded | Installment and student loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	55,559	60,414
Not graded | Real Estate and Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	221,653	87,990
Pass | Commercial Real Estate | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	10,489	9,752
Pass | Commercial Real Estate | Home improvement and home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	14	15
Pass | Installment and student loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	475	570
Pass | Real Estate and Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	10,978	10,337
Special mention | Commercial Real Estate | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Special mention | Commercial Real Estate | Home improvement and home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Special mention | Installment and student loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	11
Special mention | Real Estate and Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	11
Substandard | Commercial Real Estate | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Substandard | Commercial Real Estate | Home improvement and home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Substandard | Installment and student loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	156	513
Substandard | Real Estate and Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	156	513
Doubtful | Commercial Real Estate | Residential mortgages
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Doubtful | Commercial Real Estate | Home improvement and home equity loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Doubtful | Installment and student loans
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	0	0
Doubtful | Real Estate and Consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Loans outstanding	$ 0	$ 0
Minimum | Grades 4 and 5 – pass
Financing Receivable, Credit Quality Indicator [Line Items]
Notes receivable, period of loss recognition	3 years
Maximum | Grades 4 and 5 – pass
Financing Receivable, Credit Quality Indicator [Line Items]
Notes receivable, period of loss recognition	4 years