Loans and Allowance for Loan Losses (Troubled Debt Restructuring) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 loans	Dec. 31, 2013 loans	Dec. 31, 2012 loans
Financing Receivable, Modifications [Line Items]
Number of loans	25	19	17
Pre-modification outstanding recorded investment	$ 6,398	$ 9,043	$ 3,562
Post-modification outstanding recorded investment	6,390	8,814	2,694
Number of loans modified, extended terms	8	3
Number of loans modified, interest rate		2
Number of loans modified, extended terms and interest rate	17	14
Commercial and agricultural [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	2	0	1
Pre-modification outstanding recorded investment	94	0	312
Post-modification outstanding recorded investment	94	0	127
Real estate - construction [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	4	2	8
Pre-modification outstanding recorded investment	1,607	125	1,994
Post-modification outstanding recorded investment	1,607	125	1,335
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	11	12	3
Pre-modification outstanding recorded investment	1,227	3,387	566
Post-modification outstanding recorded investment	1,303	3,451	565
Real estate - mortgage, commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	8	5	5
Pre-modification outstanding recorded investment	3,470	5,531	690
Post-modification outstanding recorded investment	3,386	5,238	667
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	0		0
Pre-modification outstanding recorded investment	0		0
Post-modification outstanding recorded investment	$ 0		$ 0

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Amount of investment in financing receivables (after modification) modified by troubled debt restructurings.

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