The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Loans - Allowances for Loan Losses and Ending Balances by Portfolio Class and Based on Impairment Method (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	$ 236		$ 30
Allowance for loan losses collectively evaluated for impairment	7,409		8,244
Total ending allowance balance	7,645	$ 7,875	8,274	$ 8,355	$ 7,835	$ 7,017
Loans individually evaluated for impairment	3,319		6,332
Loans collectively evaluated for impairment	543,125		603,538
Total ending loans balance	546,444		609,870
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	211		4
Allowance for loan losses collectively evaluated for impairment	1,138		1,735
Total ending allowance balance	1,349	1,335	1,739	1,846	2,266	2,408
Loans individually evaluated for impairment	413		2,560
Loans collectively evaluated for impairment	128,240		188,980
Total ending loans balance	128,653		191,540
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	20		20
Allowance for loan losses collectively evaluated for impairment	3,104		3,449
Total ending allowance balance	3,124	3,404	3,469	3,321	2,781	2,153
Loans individually evaluated for impairment	1,974		2,875
Loans collectively evaluated for impairment	188,579		184,346
Total ending loans balance	190,553		187,221
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	2		1
Allowance for loan losses collectively evaluated for impairment	1,028		1,155
Total ending allowance balance	1,030	1,060	1,156	1,196	1,585	1,152
Loans individually evaluated for impairment	805		756
Loans collectively evaluated for impairment	167,758		176,399
Total ending loans balance	168,563		177,155
Construction & Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses collectively evaluated for impairment	1,275		756
Total ending allowance balance	1,275	767	756	566	337	203
Loans collectively evaluated for impairment	42,319		36,038
Total ending loans balance	42,319		36,038
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	3		5
Allowance for loan losses collectively evaluated for impairment	239		347
Total ending allowance balance	242	278	352	414	516	481
Loans individually evaluated for impairment	127		141
Loans collectively evaluated for impairment	16,229		17,775
Total ending loans balance	16,356		17,916
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses collectively evaluated for impairment	625		802
Total ending allowance balance	$ 625	$ 1,031	$ 802	$ 1,012	$ 350	$ 620