Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015
Ending allowance balance attributable to loans:
Individually evaluated for impairment	$ 2,368	$ 2,179
Collectively evaluated for impairment	10,537	10,717
Total ending allowance balance	12,905	12,896	$ 12,382	$ 12,044
Loans:
Individually evaluated for impairment	15,560	15,976
Collectively evaluated for impairment	1,096,864	1,078,962
Total	1,112,424	1,094,938
Commercial, financial, and agricultural
Ending allowance balance attributable to loans:
Individually evaluated for impairment	74	74
Collectively evaluated for impairment	1,367	1,480
Total ending allowance balance	1,441	1,554	1,254	1,532
Loans:
Individually evaluated for impairment	184	241
Collectively evaluated for impairment	141,878	145,869
Total	142,062	146,110
Real estate mortgage \| Residential
Ending allowance balance attributable to loans:
Individually evaluated for impairment	567	437
Collectively evaluated for impairment	5,004	4,946
Total ending allowance balance	5,571	5,383	5,123	5,116
Loans:
Individually evaluated for impairment	3,237	3,477
Collectively evaluated for impairment	561,974	561,263
Total	565,211	564,740
Real estate mortgage \| Commercial
Ending allowance balance attributable to loans:
Individually evaluated for impairment	1,723	1,668
Collectively evaluated for impairment	2,743	3,307
Total ending allowance balance	4,466	4,975	4,472	4,217
Loans:
Individually evaluated for impairment	12,135	12,258
Collectively evaluated for impairment	300,050	293,924
Total	312,185	306,182
Real estate mortgage \| Construction
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	187	178
Total ending allowance balance	187	178	147	160
Loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	37,390	34,650
Total	37,390	34,650
Installment loans to individuals
Ending allowance balance attributable to loans:
Individually evaluated for impairment	4	0
Collectively evaluated for impairment	544	416
Total ending allowance balance	548	416	264	243
Loans:
Individually evaluated for impairment	4	0
Collectively evaluated for impairment	55,572	43,256
Total	55,576	43,256
Unallocated Financing Receivables [Member]
Ending allowance balance attributable to loans:
Individually evaluated for impairment	0	0
Collectively evaluated for impairment	692	390
Total ending allowance balance	$ 692	$ 390	$ 1,122	$ 776

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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The balance of financing receivables 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.

+ 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

Reference 2: 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

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
-Subsection 1

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. 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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