Allowance for Loan Losses - Allowance and Loans by Impairment Methodology (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015	Dec. 31, 2014
Changes in the allowance for loan losses
Ending balance	$ 35,838	$ 35,569	$ 35,697	$ 35,606
Ending balance: individually evaluated for impairment	892	849
Ending balance, collectively evaluated for impairment	34,911	34,685
Ending balance: acquired loans - purchase credit impaired	35	35
Loans:
Ending balance	925,010	901,461
Ending balance: individually evaluated for impairment	5,662	5,344
Ending balance: collectively evaluated for impairment	906,578	882,209
Ending balance: acquired loans - purchase credit impaired	12,770	13,908
Real estate - residential mortgage
Changes in the allowance for loan losses
Ending balance	2,487	2,471	2,470	2,313
Ending balance: individually evaluated for impairment	344	360
Ending balance, collectively evaluated for impairment	2,143	2,111
Loans:
Ending balance	184,860	186,763
Ending balance: individually evaluated for impairment	2,700	2,689
Ending balance: collectively evaluated for impairment	180,972	182,769
Ending balance: acquired loans - purchase credit impaired	1,188	1,305
Real estate - construction
Changes in the allowance for loan losses
Ending balance	286	94	434	434
Ending balance, collectively evaluated for impairment	286	94
Loans:
Ending balance	27,214	7,759
Ending balance: collectively evaluated for impairment	27,214	7,759
Commercial, financial and agricultural
Changes in the allowance for loan losses
Ending balance	7,654	7,755	7,739	7,744
Ending balance: individually evaluated for impairment	474	466
Ending balance, collectively evaluated for impairment	7,145	7,254
Ending balance: acquired loans - purchase credit impaired	35	35
Loans:
Ending balance	364,708	356,062
Ending balance: individually evaluated for impairment	2,434	2,418
Ending balance: collectively evaluated for impairment	350,970	341,327
Ending balance: acquired loans - purchase credit impaired	11,304	12,317
Equity lines
Changes in the allowance for loan losses
Ending balance	1,088	1,052	812	812
Ending balance, collectively evaluated for impairment	1,088	1,052
Loans:
Ending balance	49,901	50,111
Ending balance: individually evaluated for impairment	30	30
Ending balance: collectively evaluated for impairment	49,593	49,795
Ending balance: acquired loans - purchase credit impaired	278	286
Consumer Loan
Changes in the allowance for loan losses
Ending balance	252	243	193	211
Ending balance: individually evaluated for impairment	74	23
Ending balance, collectively evaluated for impairment	178	220
Loans:
Ending balance	9,139	9,011
Ending balance: individually evaluated for impairment	498	207
Ending balance: collectively evaluated for impairment	8,641	8,804
Consumer Finance
Changes in the allowance for loan losses
Ending balance	24,071	23,954	$ 24,049	$ 24,092
Ending balance, collectively evaluated for impairment	24,071	23,954
Loans:
Ending balance	289,188	291,755
Ending balance: collectively evaluated for impairment	$ 289,188	$ 291,755

The balance of financing receivables that were acquired with deteriorated credit quality.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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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=35738203&loc=SL6953423-111524

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The valuation allowance for financing receivables acquired with deteriorated credit quality.

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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=35738203&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=35738203&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=35738203&loc=SL6953423-111524

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

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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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-Name Accounting Standards Codification
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