LOANS AND THE ALLOWANCE FOR CREDIT LOSSES - Loan Loss Experience and Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Loan loss experience and activity in allowance for loan losses
Beginning balance	$ 12,173	$ 12,014	$ 12,040	$ 11,833
Charge-offs	(40)	(23)	(158)	(115)
Recoveries	33	50	69	91
Provision (credit)	254	121	469	353
Ending balance	12,420	12,162	12,420	12,162
Additional disclosures
Provision for credit losses	200	100	405	100
Excess credit reserves	54	21	64	253
Commercial, financial and agricultural
Loan loss experience and activity in allowance for loan losses
Beginning balance	2,856	2,866	2,696	2,583
Charge-offs	(4)	(6)	(7)	(17)
Recoveries	2	14	4	28
Provision (credit)	344	51	505	331
Ending balance	3,198	2,925	3,198	2,925
Municipal
Loan loss experience and activity in allowance for loan losses
Beginning balance	622	530	590	623
Provision (credit)	(270)	(171)	(238)	(264)
Ending balance	352	359	352	359
Real estate loans - residential
Loan loss experience and activity in allowance for loan losses
Beginning balance	2,857	3,024	2,882	3,038
Charge-offs			(73)	(55)
Recoveries	11	26	22	29
Provision (credit)	(59)	(7)	(22)	31
Ending balance	2,809	3,043	2,809	3,043
Real estate loans - commercial
Loan loss experience and activity in allowance for loan losses
Beginning balance	5,281	5,149	5,386	5,209
Recoveries			4	1
Provision (credit)	142	150	33	89
Ending balance	5,423	5,299	5,423	5,299
Real estate loans - construction
Loan loss experience and activity in allowance for loan losses
Beginning balance	465	364	420	325
Provision (credit)	84	113	129	152
Ending balance	549	477	549	477
Installment
Loan loss experience and activity in allowance for loan losses
Beginning balance	92	81	66	13
Charge-offs	(36)	(17)	(78)	(43)
Recoveries	20	10	39	33
Provision (credit)	13	(15)	62	56
Ending balance	$ 89	$ 59	$ 89	59
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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