Allowance for Loan Losses - Impaired Loans Excluding PCI Loans - Recorded Investment and Unpaid Principal Balances (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2022	Dec. 31, 2022
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Recorded Investment			$ 467
Impaired financing receivables, with no related allowance recorded, Unpaid Principal Balance			492
Impaired financing receivables, with no related allowance recorded, Average Recorded Investment			1,289
Impaired financing receivables, with no related allowance recorded, Interest Income Recognized			73
Impaired financing receivables, with an allowance recorded, Recorded Investment			157
Impaired financing receivables, with an allowance recorded, Unpaid Principal Balance			161
Impaired financing receivables, with an allowance recorded, Related Allowance			7
Impaired financing receivables, with an allowance recorded, Average Recorded Investment			233
Impaired financing receivables, Recorded Investment, Total			624
Impaired financing receivables, Unpaid Principal Balance, Total			653
Impaired financing receivables, Related Allowance, Total			7
Impaired financing receivables, Average Recorded Investment, Total	$ 1,496	$ 1,367	1,522
Impaired financing receivables, Interest Income Recognized, Total	14	43	73
Commercial and Agriculture [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Average Recorded Investment			86
Impaired financing receivables, with no related allowance recorded, Interest Income Recognized			3
Impaired financing receivables, Average Recorded Investment, Total	172	86	86
Impaired financing receivables, Interest Income Recognized, Total			3
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Recorded Investment			82
Impaired financing receivables, with no related allowance recorded, Unpaid Principal Balance			82
Impaired financing receivables, with no related allowance recorded, Average Recorded Investment			192
Impaired financing receivables, with no related allowance recorded, Interest Income Recognized			22
Impaired financing receivables, with an allowance recorded, Recorded Investment			150
Impaired financing receivables, with an allowance recorded, Unpaid Principal Balance			150
Impaired financing receivables, with an allowance recorded, Related Allowance			6
Impaired financing receivables, with an allowance recorded, Average Recorded Investment			214
Impaired financing receivables, Recorded Investment, Total			232
Impaired financing receivables, Unpaid Principal Balance, Total			232
Impaired financing receivables, Related Allowance, Total			6
Impaired financing receivables, Average Recorded Investment, Total	504	349	406
Impaired financing receivables, Interest Income Recognized, Total	3	10	22
Commercial Real Estate Non Owner Occupied [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Average Recorded Investment			35
Impaired financing receivables, with no related allowance recorded, Interest Income Recognized			1
Impaired financing receivables, Average Recorded Investment, Total	70	35	35
Impaired financing receivables, Interest Income Recognized, Total			1
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Recorded Investment			385
Impaired financing receivables, with no related allowance recorded, Unpaid Principal Balance			410
Impaired financing receivables, with no related allowance recorded, Average Recorded Investment			595
Impaired financing receivables, with no related allowance recorded, Interest Income Recognized			33
Impaired financing receivables, with an allowance recorded, Recorded Investment			7
Impaired financing receivables, with an allowance recorded, Unpaid Principal Balance			11
Impaired financing receivables, with an allowance recorded, Related Allowance			1
Impaired financing receivables, with an allowance recorded, Average Recorded Investment			19
Impaired financing receivables, Recorded Investment, Total			392
Impaired financing receivables, Unpaid Principal Balance, Total			421
Impaired financing receivables, Related Allowance, Total			1
Impaired financing receivables, Average Recorded Investment, Total	503	516	614
Impaired financing receivables, Interest Income Recognized, Total	9	19	33
Lease Financing Receivables [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, Average Recorded Investment, Total			381
Impaired financing receivables, Interest Income Recognized, Total			14
Farm Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Average Recorded Investment			381
Impaired financing receivables, with no related allowance recorded, Interest Income Recognized			$ 14
Impaired financing receivables, Average Recorded Investment, Total	247	381
Impaired financing receivables, Interest Income Recognized, Total	$ 2	$ 14

Impaired financing receivable with and no related allowance.

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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