Loans - Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Impaired loans
Impaired loans, Unpaid Principal Balance	$ 6,005	$ 5,688
Impaired loans, Recorded Investment in Loans without Specific Reserve	260	264
Impaired loans, Recorded Investment in Loans with Specific Reserve	5,402	5,080,000
Impaired loans, Related Allowance	892	849
Impaired loans, Average Balance	5,692	5,425
Impaired loans, Interest Income Recognized	40	141
Real estate - residential mortgage
Impaired loans
Impaired loans, Unpaid Principal Balance	2,811	2,828
Impaired loans, Recorded Investment in Loans without Specific Reserve	172	173
Impaired loans, Recorded Investment in Loans with Specific Reserve	2,528	2,516,000
Impaired loans, Related Allowance	344	360
Impaired loans, Average Balance	2,708	2,718
Impaired loans, Interest Income Recognized	26	97
Commercial, financial and agricultural \| Commercial real estate lending
Impaired loans
Impaired loans, Unpaid Principal Balance	2,475	2,522
Impaired loans, Recorded Investment in Loans without Specific Reserve	58	61
Impaired loans, Recorded Investment in Loans with Specific Reserve	2,190	2,258,000
Impaired loans, Related Allowance	435	438
Impaired loans, Average Balance	2,265	2,361
Impaired loans, Interest Income Recognized	8	35
Commercial, financial and agricultural \| Commercial business lending
Impaired loans
Impaired loans, Unpaid Principal Balance	189	99
Impaired loans, Recorded Investment in Loans with Specific Reserve	186	99,000
Impaired loans, Related Allowance	39	28
Impaired loans, Average Balance	191	108
Impaired loans, Interest Income Recognized	2	1
Equity lines
Impaired loans
Impaired loans, Unpaid Principal Balance	32	32
Impaired loans, Recorded Investment in Loans without Specific Reserve	30	30
Impaired loans, Average Balance	30	30
Impaired loans, Interest Income Recognized		1
Consumer Loan
Impaired loans
Impaired loans, Unpaid Principal Balance	498	207
Impaired loans, Recorded Investment in Loans with Specific Reserve	498	207,000
Impaired loans, Related Allowance	74	23
Impaired loans, Average Balance	498	208
Impaired loans, Interest Income Recognized	4	$ 7
PCI Loans
Impaired loans
Impaired loans, Unpaid Principal Balance	24,400
Acquired Loans	$ 12,800

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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