Allowance for Loan Losses - Impaired Financing Receivables Excluding PCI Loans - Recorded Investment and Unpaid Principal Balances (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Recorded Investment	$ 467	$ 1,012
Impaired financing receivables, with no related allowance recorded, Unpaid Principal Balance	492	1,037
Impaired financing receivables, with an allowance recorded, Recorded Investment	157	210
Impaired financing receivables, with an allowance recorded, Unpaid Principal Balance	161	214
Impaired financing receivables, with an allowance recorded, Related Allowance	7	18
Impaired financing receivables, Recorded Investment, Total	624	1,222
Impaired financing receivables, Unpaid Principal Balance, Total	653	1,251
Impaired financing receivables, Related Allowance, Total	7	18
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 an allowance recorded, Recorded Investment	150	187
Impaired financing receivables, with an allowance recorded, Unpaid Principal Balance	150	187
Impaired financing receivables, with an allowance recorded, Related Allowance	6	7
Impaired financing receivables, Recorded Investment, Total	232	187
Impaired financing receivables, Unpaid Principal Balance, Total	232	187
Impaired financing receivables, Related Allowance, Total	6	7
Residential Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Recorded Investment	385	503
Impaired financing receivables, with no related allowance recorded, Unpaid Principal Balance	410	528
Impaired financing receivables, with an allowance recorded, Recorded Investment	7	23
Impaired financing receivables, with an allowance recorded, Unpaid Principal Balance	11	27
Impaired financing receivables, with an allowance recorded, Related Allowance	1	11
Impaired financing receivables, Recorded Investment, Total	392	526
Impaired financing receivables, Unpaid Principal Balance, Total	421	555
Impaired financing receivables, Related Allowance, Total	$ 1	11
Farm Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Impaired financing receivables, with no related allowance recorded, Recorded Investment		509
Impaired financing receivables, with no related allowance recorded, Unpaid Principal Balance		509
Impaired financing receivables, Recorded Investment, Total		509
Impaired financing receivables, Unpaid Principal Balance, Total		$ 509

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.

+ Details

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- Definition

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 14A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=SL6953550-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Amount of allowance for credit losses related to recorded investment.

+ 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 (a)(3)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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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

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 (a)(4)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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- Definition

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

+ References

+ Details

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no 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 (a)(4)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

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- Definition

Unpaid principal balance of impaired financing receivables for which there is 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 (a)(4)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

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