Loans - Impaired Loans (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Impaired loans
Impaired loans, troubled debt restructurings	$ 5,830,000	$ 5,620,000
Impaired loans, Recorded Investment	6,014,000	6,262,000
Impaired loans, Unpaid Principal Balance	6,232,000	6,471,000
Impaired loans, Related Allowance	879,000	1,043,000
Impaired loans, Average Balance	5,901,000	5,542,000
Impaired loans, Interest Income Recognized	302,000	219,000
Real estate - residential mortgage
Impaired loans
Impaired loans, Recorded Investment	3,000,000	2,601,000
Impaired loans, Unpaid Principal Balance	3,094,000	2,694,000
Impaired loans, Related Allowance	417,000	390,000
Impaired loans, Average Balance	2,931,000	2,090,000
Impaired loans, Interest Income Recognized	139,000	99,000
Commercial, financial and agricultural \| Commercial real estate lending
Impaired loans
Impaired loans, Recorded Investment	2,786,000	2,729,000
Impaired loans, Unpaid Principal Balance	2,908,000	2,780,000
Impaired loans, Related Allowance	440,000	504,000
Impaired loans, Average Balance	2,735,000	2,748,000
Impaired loans, Interest Income Recognized	150,000	99,000
Commercial, financial and agricultural \| Builder line lending
Impaired loans
Impaired loans, Recorded Investment		13,000
Impaired loans, Unpaid Principal Balance		16,000
Impaired loans, Related Allowance		4,000
Impaired loans, Average Balance		14,000
Impaired loans, Interest Income Recognized		1,000
Commercial, financial and agricultural \| Commercial business lending
Impaired loans
Impaired loans, Recorded Investment	103,000	695,000
Impaired loans, Unpaid Principal Balance	103,000	756,000
Impaired loans, Related Allowance	15,000	131,000
Impaired loans, Average Balance	115,000	562,000
Impaired loans, Interest Income Recognized	7,000	11,000
Equity lines
Impaired loans
Impaired loans, Recorded Investment	30,000	131,000
Impaired loans, Unpaid Principal Balance	32,000	132,000
Impaired loans, Related Allowance	1,000
Impaired loans, Average Balance	25,000	33,000
Impaired loans, Interest Income Recognized	2,000
Consumer Loan
Impaired loans
Impaired loans, Recorded Investment	95,000	93,000
Impaired loans, Unpaid Principal Balance	95,000	93,000
Impaired loans, Related Allowance	6,000	14,000
Impaired loans, Average Balance	95,000	95,000
Impaired loans, Interest Income Recognized	$ 4,000	$ 9,000

Financing Receivables Impaired Troubled Debt Restructuring Amount

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ 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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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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Amount of allowance for credit losses related to recorded investment.

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- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

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