LOANS AND THE ALLOWANCE FOR CREDIT LOSSES - Allowance for Loan Losses and Recorded Investment in Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Loan loss experience and activity in allowance for loan losses
Ending balance individually evaluated for impairment	$ 245	$ 184
Ending balance collectively evaluated for impairment	12,935	12,475
Total allowance for credit losses	13,187	12,659	$ 12,173	$ 12,040
Financing receivables, Ending balance individually evaluated for impairment	3,590	2,956
Financing receivables, Ending balance collectively evaluated for impairment	1,536,563	1,508,607
Total	1,542,718	1,514,209
Receivables acquired with deteriorated credit quality
Loan loss experience and activity in allowance for loan losses
Total allowance for credit losses	7
Total	2,565	2,646
Commercial, financial and agricultural
Loan loss experience and activity in allowance for loan losses
Ending balance collectively evaluated for impairment	3,195	2,946
Total allowance for credit losses	3,195	2,946	2,856	2,696
Financing receivables, Ending balance individually evaluated for impairment	77	97
Financing receivables, Ending balance collectively evaluated for impairment	276,144	256,239
Total	276,915	257,078
Commercial, financial and agricultural \| Receivables acquired with deteriorated credit quality
Loan loss experience and activity in allowance for loan losses
Total	694	742
Municipal
Loan loss experience and activity in allowance for loan losses
Ending balance collectively evaluated for impairment	574	593
Total allowance for credit losses	574	593	622	590
Financing receivables, Ending balance collectively evaluated for impairment	113,875	114,509
Total	113,875	114,509
Real estate loans - residential
Loan loss experience and activity in allowance for loan losses
Ending balance individually evaluated for impairment	227	184
Ending balance collectively evaluated for impairment	2,325	2,391
Total allowance for credit losses	2,552	2,575	2,857	2,882
Financing receivables, Ending balance individually evaluated for impairment	1,447	1,213
Financing receivables, Ending balance collectively evaluated for impairment	436,977	446,314
Total	438,424	447,527
Real estate loans - commercial
Loan loss experience and activity in allowance for loan losses
Ending balance individually evaluated for impairment	18
Ending balance collectively evaluated for impairment	6,331	5,922
Total allowance for credit losses	6,356	5,922	5,281	5,386
Financing receivables, Ending balance individually evaluated for impairment	2,066	1,634
Financing receivables, Ending balance collectively evaluated for impairment	668,775	633,217
Total	672,712	636,755
Real estate loans - commercial \| Receivables acquired with deteriorated credit quality
Loan loss experience and activity in allowance for loan losses
Total allowance for credit losses	7
Total	1,871	1,904
Real estate loans - construction
Loan loss experience and activity in allowance for loan losses
Ending balance collectively evaluated for impairment	351	534
Total allowance for credit losses	351	534	465	420
Financing receivables, Ending balance collectively evaluated for impairment	35,964	52,533
Total	35,964	52,533
Installment
Loan loss experience and activity in allowance for loan losses
Ending balance collectively evaluated for impairment	159	89
Total allowance for credit losses	159	89	$ 92	$ 66
Financing receivables, Ending balance individually evaluated for impairment		12
Financing receivables, Ending balance collectively evaluated for impairment	4,813	5,778
Total	4,813	5,790
All other loans
Loan loss experience and activity in allowance for loan losses
Financing receivables, Ending balance collectively evaluated for impairment	15	17
Total	$ 15	$ 17

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

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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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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The balance of financing receivables that were collectively evaluated for impairment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4428-111522

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