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Loans and Allowance for Credit Losses - Troubled Debt Restructurings Identified During Period (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) Contract	Dec. 31, 2021 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract	5	30
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 693	$ 9,370
Financing Receivable, Troubled Debt Restructuring	676	1,690
Financing Receivable Troubled Debt Restructuring Specific Reserve	0	0
Contractual Payment Modification [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	683	8,901
Contractual Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	10	469
Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	$ 0
Commercial Loan [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		6
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 7,893
Financing Receivable, Troubled Debt Restructuring		288
Financing Receivable Troubled Debt Restructuring Specific Reserve		$ 0
Commercial Loan [Member] | Time and demand loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		6
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 7,893
Financing Receivable, Troubled Debt Restructuring		288
Financing Receivable Troubled Debt Restructuring Specific Reserve		0
Commercial Loan [Member] | Contractual Payment Modification [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		7,893
Commercial Loan [Member] | Contractual Payment Modification [Member] | Time and demand loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		7,893
Commercial Loan [Member] | Contractual Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Commercial Loan [Member] | Contractual Interest Rate Reduction [Member] | Time and demand loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Commercial Loan [Member] | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Commercial Loan [Member] | Extended Maturity [Member] | Time and demand loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 0
Residential Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract	5	15
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 693	$ 660
Financing Receivable, Troubled Debt Restructuring	676	624
Financing Receivable Troubled Debt Restructuring Specific Reserve	$ 0	$ 0
Residential Real Estate [Member] | Senior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract	5	12
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 693	$ 530
Financing Receivable, Troubled Debt Restructuring	676	502
Financing Receivable Troubled Debt Restructuring Specific Reserve	0	$ 0
Residential Real Estate [Member] | Junior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		3
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 130
Financing Receivable, Troubled Debt Restructuring		122
Financing Receivable Troubled Debt Restructuring Specific Reserve		0
Residential Real Estate [Member] | Contractual Payment Modification [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	683	301
Residential Real Estate [Member] | Contractual Payment Modification [Member] | Senior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	683	171
Residential Real Estate [Member] | Contractual Payment Modification [Member] | Junior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		130
Residential Real Estate [Member] | Contractual Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	10	359
Residential Real Estate [Member] | Contractual Interest Rate Reduction [Member] | Senior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	10	359
Residential Real Estate [Member] | Contractual Interest Rate Reduction [Member] | Junior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Residential Real Estate [Member] | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	0	0
Residential Real Estate [Member] | Extended Maturity [Member] | Senior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification	$ 0	0
Residential Real Estate [Member] | Extended Maturity [Member] | Junior Lien
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 0
Commercial Real Estate [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		2
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 644
Financing Receivable, Troubled Debt Restructuring		634
Financing Receivable Troubled Debt Restructuring Specific Reserve		$ 0
Commercial Real Estate [Member] | Nonowner Occupied Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		2
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 644
Financing Receivable, Troubled Debt Restructuring		634
Financing Receivable Troubled Debt Restructuring Specific Reserve		0
Commercial Real Estate [Member] | Contractual Payment Modification [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		644
Commercial Real Estate [Member] | Contractual Payment Modification [Member] | Nonowner Occupied Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		644
Commercial Real Estate [Member] | Contractual Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Commercial Real Estate [Member] | Contractual Interest Rate Reduction [Member] | Nonowner Occupied Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Commercial Real Estate [Member] | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Commercial Real Estate [Member] | Extended Maturity [Member] | Nonowner Occupied Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 0
Loans To Individuals [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		7
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 173
Financing Receivable, Troubled Debt Restructuring		144
Financing Receivable Troubled Debt Restructuring Specific Reserve		$ 0
Loans To Individuals [Member] | Automobiles
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Modifications, Number of Contracts | Contract		7
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 173
Financing Receivable, Troubled Debt Restructuring		144
Financing Receivable Troubled Debt Restructuring Specific Reserve		0
Loans To Individuals [Member] | Contractual Payment Modification [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		63
Loans To Individuals [Member] | Contractual Payment Modification [Member] | Automobiles
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		63
Loans To Individuals [Member] | Contractual Interest Rate Reduction [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		110
Loans To Individuals [Member] | Contractual Interest Rate Reduction [Member] | Automobiles
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		110
Loans To Individuals [Member] | Extended Maturity [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		0
Loans To Individuals [Member] | Extended Maturity [Member] | Automobiles
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing Receivable, Troubled Debt Restructuring, Premodification		$ 0

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- Definition

Specific reserve related to troubled debt restructurings identified during the period.

+ References

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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