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, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	$ 36		$ 101
Allowance for loan losses collectively evaluated for impairment	6,740		5,806
Total ending allowance balance	6,776	$ 6,537	5,907	$ 6,204	$ 5,918	$ 5,604
Loans individually evaluated for impairment	6,014		3,852
Loans collectively evaluated for impairment	559,678		544,553
Total ending loans balance	565,692		548,405
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	18		36
Allowance for loan losses collectively evaluated for impairment	2,325		2,142
Total ending allowance balance	2,343	2,267	2,178	1,980	1,849	1,813
Loans individually evaluated for impairment	2,441		419
Loans collectively evaluated for impairment	138,394		146,456
Total ending loans balance	140,835		146,875
Commercial Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	17		64
Allowance for loan losses collectively evaluated for impairment	2,021		1,727
Total ending allowance balance	2,038	1,946	1,791	1,664	1,612	1,735
Loans individually evaluated for impairment	2,694		2,403
Loans collectively evaluated for impairment	209,983		181,202
Total ending loans balance	212,677		183,605
Residential Real Estate [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses individually evaluated for impairment	1		1
Allowance for loan losses collectively evaluated for impairment	1,156		1,244
Total ending allowance balance	1,157	1,229	1,245	1,275	1,236	1,273
Loans individually evaluated for impairment	865		1,030
Loans collectively evaluated for impairment	176,119		166,266
Total ending loans balance	176,984		167,296
Construction & Land Development [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses collectively evaluated for impairment	116		258
Total ending allowance balance	116	104	258	287	279	237
Loans collectively evaluated for impairment	14,946		31,227
Total ending loans balance	14,946		31,227
Consumer [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses collectively evaluated for impairment	333		306
Total ending allowance balance	333	341	306	237	259	175
Loans individually evaluated for impairment	14
Loans collectively evaluated for impairment	20,236		19,402
Total ending loans balance	20,250		19,402
Unallocated [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Allowance for loan losses collectively evaluated for impairment	789		129
Total ending allowance balance	$ 789	$ 650	$ 129	$ 761	$ 683	$ 371