LOANS AND ALLOWANCE FOR LOAN LOSSES - Allowances (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Dec. 31, 2018
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	$ 18,944	$ 21,161
Charge-offs	(448)	(571)
Recoveries	156	91
Net recoveries (charge-offs)	(292)	(480)
Provision for loan losses	1,093	709
Ending balance	19,745	21,390
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment			$ 3,976	$ 2,189
Collectively evaluated for impairment			15,769	16,755
Total ending allowance balance	18,944	21,161	19,745	18,944
Loans [Abstract]
Loans individually evaluated for impairment			11,973	8,731
Loans collectively evaluated for impairment			1,291,059	1,306,878
Total recorded investment in loans			1,303,032	1,315,609
Commercial and Agricultural
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	5,383	6,976
Charge-offs	(7)	(19)
Recoveries	11	9
Net recoveries (charge-offs)	4	(10)
Provision for loan losses	42	37
Ending balance	5,429	7,003
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment			1,748	1,743
Collectively evaluated for impairment			3,681	3,640
Total ending allowance balance	5,383	6,976	5,429	5,383
Loans [Abstract]
Loans individually evaluated for impairment			2,136	2,128
Loans collectively evaluated for impairment			203,001	201,284
Total recorded investment in loans			205,137	203,412
Commercial Mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	8,184	8,514
Charge-offs	0	0
Recoveries	1	1
Net recoveries (charge-offs)	1	1
Provision for loan losses	1,289	125
Ending balance	9,474	8,640
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment			2,228	446
Collectively evaluated for impairment			7,246	7,738
Total ending allowance balance	8,184	8,514	9,474	8,184
Loans [Abstract]
Loans individually evaluated for impairment			9,278	6,146
Loans collectively evaluated for impairment			650,880	656,842
Total recorded investment in loans			660,158	662,988
Residential mortgages
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	1,226	1,316
Charge-offs	(2)	(94)
Recoveries	0	5
Net recoveries (charge-offs)	(2)	(89)
Provision for loan losses	(9)	180
Ending balance	1,215	1,407
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			1,215	1,226
Total ending allowance balance	1,226	1,316	1,215	1,226
Loans [Abstract]
Loans individually evaluated for impairment			392	402
Loans collectively evaluated for impairment			181,548	182,823
Total recorded investment in loans			181,940	183,225
Consumer Loans
Allowance for loan losses, by portfolio segment [Roll Forward]
Beginning balance	4,151	4,355
Charge-offs	(439)	(458)
Recoveries	144	76
Net recoveries (charge-offs)	(295)	(382)
Provision for loan losses	(229)	367
Ending balance	3,627	4,340
Ending allowance balance attributable to loans [Abstract]
Individually evaluated for impairment			0	0
Collectively evaluated for impairment			3,627	4,151
Total ending allowance balance	$ 4,151	$ 4,355	3,627	4,151
Loans [Abstract]
Loans individually evaluated for impairment			167	55
Loans collectively evaluated for impairment			255,630	265,929
Total recorded investment in loans			$ 255,797	$ 265,984

No definition available.

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- Definition

Amount of recovery of (write-downs of) financing receivables doubtful of collection.

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No definition available.

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A valuation allowance for financing receivables that are expected to be uncollectible.

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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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Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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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Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

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Amount of expense related to estimated loss from loan and lease transactions.

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