LOANS AND ALLOWANCE FOR LOAN LOSSES - Summary of Ending Loan Balances Evaluated for Impairment and Related Allowance for Loan Losses Allocation (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	$ 7,300	$ 7,973
Loans, Collectively evaluated for impairment	894,031	875,418
Total Loans	901,331	883,391
Allowance for loan losses, Individually evaluated for impairment	132	43
Allowance for loan losses, Collectively evaluated for impairment	12,536	12,732
Allowance for loan losses, Total	12,668	12,775	$ 13,347	$ 13,568
Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Loans	90,638	88,465
Municipal
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Loans	53,225	53,741
Installment and Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Total Loans	7,376	7,118
Commercial
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	2,184	3,052
Loans, Collectively evaluated for impairment	612,411	598,769
Total Loans	614,595	601,821
Allowance for loan losses, Individually evaluated for impairment	91	0
Allowance for loan losses, Collectively evaluated for impairment	8,709	9,238
Allowance for loan losses, Total	8,800	9,238	9,827	9,803
Commercial \| Commercial Real Estate
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	1,707	2,457
Loans, Collectively evaluated for impairment	435,587	426,410
Total Loans	437,294	428,867
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	6,963	7,530
Allowance for loan losses, Total	6,963	7,530	7,996	7,883
Commercial \| Acquisition and Development
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	0	1
Loans, Collectively evaluated for impairment	33,438	30,747
Total Loans	33,438	30,748
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	513	580
Allowance for loan losses, Total	513	580	739	850
Commercial \| Commercial and Industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	477	594
Loans, Collectively evaluated for impairment	90,161	87,871
Total Loans	90,638	88,465
Allowance for loan losses, Individually evaluated for impairment	91	0
Allowance for loan losses, Collectively evaluated for impairment	1,127	1,074
Allowance for loan losses, Total	1,218	1,074	1,030	1,012
Commercial \| Municipal
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	53,225	53,741
Total Loans	53,225	53,741
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	106	54
Allowance for loan losses, Total	106	54	62	58
Consumer
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	5,116	4,921
Loans, Collectively evaluated for impairment	281,620	276,649
Total Loans	286,736	281,570
Allowance for loan losses, Individually evaluated for impairment	41	43
Allowance for loan losses, Collectively evaluated for impairment	3,315	3,080
Allowance for loan losses, Total	3,356	3,123	2,856	2,991
Consumer \| Residential Mortgage
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	5,111	4,915
Loans, Collectively evaluated for impairment	274,249	269,537
Total Loans	279,360	274,452
Allowance for loan losses, Individually evaluated for impairment	41	43
Allowance for loan losses, Collectively evaluated for impairment	3,188	2,936
Allowance for loan losses, Total	3,229	2,979	2,677	2,870
Consumer \| Installment and Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	5	6
Loans, Collectively evaluated for impairment	7,371	7,112
Total Loans	7,376	7,118
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	127	144
Allowance for loan losses, Total	127	144	179	121
Unallocated
Financing Receivable, Allowance for Credit Losses [Line Items]
Loans, Individually evaluated for impairment	0	0
Loans, Collectively evaluated for impairment	0	0
Total Loans	0	0
Allowance for loan losses, Individually evaluated for impairment	0	0
Allowance for loan losses, Collectively evaluated for impairment	512	414
Allowance for loan losses, Total	$ 512	$ 414	$ 664	$ 774

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively 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 and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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