Loans - Aging of recorded investment in past due loans (Details 5) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	$ 2,804	$ 3,657
90 Days or More Past Due		127
Nonaccrual Loans	16,280	14,044
Total Past Due	19,084	17,828
Loans Not Past Due	1,017,728	991,487
Loans	1,036,812	1,009,315
Commercial, financial, and agricultural
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
Loans	216,316	210,712
Commercial, financial, and agricultural | Commercial
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due		39
90 Days or More Past Due
Nonaccrual Loans	742	831
Total Past Due	742	870
Loans Not Past Due	137,587	125,735
Loans	138,329	126,605
Commercial, financial, and agricultural | Financial
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due
90 Days or More Past Due
Nonaccrual Loans
Total Past Due
Loans Not Past Due	3,871	4,678
Loans	3,871	4,678
Commercial, financial, and agricultural | Agricultural
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due
90 Days or More Past Due
Nonaccrual Loans		182
Total Past Due		182
Loans Not Past Due	10,141	10,712
Loans	10,141	10,894
Commercial, financial, and agricultural | Equity lines
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	15
90 Days or More Past Due
Nonaccrual Loans	87	75
Total Past Due	102	75
Loans Not Past Due	41,034	40,536
Loans	41,136	40,611
Commercial, financial, and agricultural | Other
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due
90 Days or More Past Due
Nonaccrual Loans	58	63
Total Past Due	58	63
Loans Not Past Due	22,781	27,861
Loans	22,839	27,924
Commercial real estate
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
Loans	381,882	366,566
Commercial real estate | Owner occupied
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	259	1,158
90 Days or More Past Due
Nonaccrual Loans	8,097	3,988
Total Past Due	8,356	5,146
Loans Not Past Due	227,853	224,217
Loans	236,209	229,363
Commercial real estate | Non Owner occupied
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	1,199	226
90 Days or More Past Due		127
Nonaccrual Loans	2,210	2,775
Total Past Due	3,409	3,128
Loans Not Past Due	142,264	134,075
Loans	145,673	137,203
Residential real estate
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
Loans	250,111	229,161
Residential real estate | Secured by first liens
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	507	2,207
90 Days or More Past Due
Nonaccrual Loans	3,963	3,192
Total Past Due	4,470	5,399
Loans Not Past Due	241,205	218,742
Loans	245,675	224,141
Residential real estate | Secured by junior liens
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	1
90 Days or More Past Due
Nonaccrual Loans	338	368
Total Past Due	339	368
Loans Not Past Due	4,097	4,652
Loans	4,436	5,020
Acquisition, development and construction
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
Loans	168,396	184,292
Acquisition, development and construction | Residential
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due
90 Days or More Past Due
Nonaccrual Loans
Total Past Due
Loans Not Past Due	53,260	54,266
Loans	53,260	54,266
Acquisition, development and construction | Other
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	778	8
90 Days or More Past Due
Nonaccrual Loans	745	2,537
Total Past Due	1,523	2,545
Loans Not Past Due	113,613	127,481
Loans	115,136	130,026
Consumer
Financing Receivable Recorded Investment Credit Quality Indicators [Line Items]
30 - 89 Days Past Due	45	19
90 Days or More Past Due
Nonaccrual Loans	40	33
Total Past Due	85	52
Loans Not Past Due	20,022	18,532
Loans	$ 20,107	$ 18,584