Loans and Allowance for Loan Losses (Troubled Debt Restructuring) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 loans	Dec. 31, 2011 loans
Financing Receivable, Modifications [Line Items]
Number of loans	17	40
Pre-modification outstanding recorded investment	$ 3,562	$ 16,114
Post-modification outstanding recorded investment	2,694	16,114
Commercial and agricultural [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	1	8
Pre-modification outstanding recorded investment	312	806
Post-modification outstanding recorded investment	127	806
Real estate - construction [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	8	8
Pre-modification outstanding recorded investment	1,994	5,162
Post-modification outstanding recorded investment	1,335	5,162
Real estate - mortgage, 1-4 family residential [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	3	9
Pre-modification outstanding recorded investment	566	406
Post-modification outstanding recorded investment	565	406
Real estate - mortgage, commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of loans	5	15
Pre-modification outstanding recorded investment	690	9,740
Post-modification outstanding recorded investment	667	9,740
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