Allowance for Loan Losses - Impaired Loans Excluding PCI Loans - Recorded Investment and Unpaid Principal Balances (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 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		60
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	$ 1,237	1,522
Impaired financing receivables, Interest Income Recognized, Total	16	60
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		6
Impaired financing receivables, Average Recorded Investment, Total		86
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 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	193	406
Impaired financing receivables, Interest Income Recognized, Total	3	6
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, Average Recorded Investment, Total		35
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		40
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	530	614
Impaired financing receivables, Interest Income Recognized, Total	7	40
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	514
Impaired financing receivables, Interest Income Recognized, Total	$ 6

Impaired financing receivable with and no related allowance.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

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- Definition

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.

+ References

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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Amount of average investment of impaired financing receivables for which there is no related allowance for credit losses.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

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Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

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