Allowances for Loan Losses - Summary of Aging Analysis of the Recorded Investment of Past-Due Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	$ 4,811	$ 5,556
Loans receivable	863,984	715,039
Total > 90 Days and Accruing	114	762
Agriculture Loans [Member]
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	0	0
Loans receivable	13,977	9,341
Total > 90 Days and Accruing	0	0
Commercial and PPP Loans [Member]
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	0	512
Loans receivable	98,475	122,378
Total > 90 Days and Accruing	13	0
Commercial Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	4,218	4,394
Loans receivable	482,367	338,749
Total > 90 Days and Accruing	73	0
Residential Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	593	650
Loans receivable	251,832	231,302
Total > 90 Days and Accruing	28	762
Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	0	0
Loans receivable	11,929	7,087
Total > 90 Days and Accruing	0	0
Municipal Loans [Member]
Financing Receivable, Past Due [Line Items]
Purchased Credit Impaired Loans	0	0
Loans receivable	5,404	6,182
Total > 90 Days and Accruing	0	0
30-59 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	1,566	1,852
30-59 Days Past Due [Member] | Agriculture Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	83
30-59 Days Past Due [Member] | Commercial and PPP Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	18	66
30-59 Days Past Due [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	245
30-59 Days Past Due [Member] | Residential Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	1,524	1,427
30-59 Days Past Due [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	24	31
30-59 Days Past Due [Member] | Municipal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	0
60-89 Days Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	780	213
60-89 Days Past Due [Member] | Agriculture Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	0
60-89 Days Past Due [Member] | Commercial and PPP Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	19	0
60-89 Days Past Due [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	0
60-89 Days Past Due [Member] | Residential Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	617	211
60-89 Days Past Due [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	2
60-89 Days Past Due [Member] | Municipal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	144	0
90 Days or Greater Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	728	869
90 Days or Greater Past Due [Member] | Agriculture Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	0
90 Days or Greater Past Due [Member] | Commercial and PPP Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	13	0
90 Days or Greater Past Due [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	262	0
90 Days or Greater Past Due [Member] | Residential Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	451	869
90 Days or Greater Past Due [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	2
90 Days or Greater Past Due [Member] | Municipal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	0
Total Past Due [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	3,074	2,934
Total Past Due [Member] | Agriculture Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	0	83
Total Past Due [Member] | Commercial and PPP Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	50	66
Total Past Due [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	262	245
Total Past Due [Member] | Residential Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	2,592	2,507
Total Past Due [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	26	33
Total Past Due [Member] | Municipal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	144	0
Current [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	856,099	706,549
Current [Member] | Agriculture Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	13,977	9,258
Current [Member] | Commercial and PPP Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	98,425	121,800
Current [Member] | Commercial Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	477,887	334,110
Current [Member] | Residential Real Estate Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	248,647	228,145
Current [Member] | Consumer Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	11,903	7,054
Current [Member] | Municipal Loans [Member]
Financing Receivable, Past Due [Line Items]
Loans, Gross	$ 5,260	$ 6,182