LOANS AND THE ALLOWANCE FOR CREDIT LOSSES - Loan Loss Experience and Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Loan loss experience and activity in allowance for loan losses
Beginning balance	$ 12,420	$ 12,162	$ 12,040	$ 11,833
Charge-offs	(247)	(62)	(405)	(177)
Recoveries	21	19	90	110
Provision (credit)	346	91	815	444
Ending balance	12,540	12,210	12,540	12,210
Additional disclosures
Provision for credit losses	500	150	905	250
Excess credit reserves	154	59	90	194
Commercial, financial and agricultural
Loan loss experience and activity in allowance for loan losses
Beginning balance	3,198	2,925	2,696	2,583
Charge-offs	(115)	(11)	(122)	(28)
Recoveries	1	3	5	31
Provision (credit)	22	(84)	527	247
Ending balance	3,106	2,833	3,106	2,833
Municipal
Loan loss experience and activity in allowance for loan losses
Beginning balance	352	359	590	623
Provision (credit)	251	272	13	8
Ending balance	603	631	603	631
Real estate loans - residential
Loan loss experience and activity in allowance for loan losses
Beginning balance	2,809	3,043	2,882	3,038
Charge-offs	(82)	(29)	(155)	(84)
Recoveries	6	7	28	36
Provision (credit)	(70)	(62)	(92)	(31)
Ending balance	2,663	2,959	2,663	2,959
Real estate loans - commercial
Loan loss experience and activity in allowance for loan losses
Beginning balance	5,423	5,299	5,386	5,209
Recoveries		1	4	2
Provision (credit)	84	(62)	117	27
Ending balance	5,507	5,238	5,507	5,238
Real estate loans - construction
Loan loss experience and activity in allowance for loan losses
Beginning balance	549	477	420	325
Provision (credit)	25	16	154	168
Ending balance	574	493	574	493
Installment
Loan loss experience and activity in allowance for loan losses
Beginning balance	89	59	66	13
Charge-offs	(50)	(22)	(128)	(65)
Recoveries	14	8	53	41
Provision (credit)	34	11	96	67
Ending balance	$ 87	$ 56	$ 87	56
All other loans
Loan loss experience and activity in allowance for loan losses
Beginning balance				42
Provision (credit)				$ (42)

Amount of excess expense related to credit loss from transactions other than loan and lease transactions.

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- Definition

Amount of expense related to the allowance for loan losses.

+ References

No definition available.

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- References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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- Definition

Amount of expense related to credit loss from transactions other than loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 11
-Article 9

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