Loans and Allowance - Summary of Troubled Debt Restructurings (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013 Loan	Jun. 30, 2012 Loan	Jun. 30, 2013 Loan	Jun. 30, 2012 Loan
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	$ 4,986	$ 3,120	$ 5,629	$ 5,361
Post-Modification Recorded Balance	4,051	2,849	4,616	4,946
Number of Loans	10	18	16	26
Commercial and industrial loans
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	36	166	133	405
Post-Modification Recorded Balance	36	166	133	405
Number of Loans	1	2	4	4
Real estate loans - Construction
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance		491		491
Post-Modification Recorded Balance		350		350
Number of Loans		1		1
Real estate loans - Commercial and farm land
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	4,474	730	4,985	2,508
Post-Modification Recorded Balance	3,550	735	3,981	2,369
Number of Loans	2	4	4	6
Real estate loans - Residential
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	432	1,733	467	1,957
Post-Modification Recorded Balance	420	1,598	457	1,822
Number of Loans	5	11	6	15
Individuals' loans for household and other personal expenditures
Financing Receivable, Modifications [Line Items]
Pre-Modification Recorded Balance	44		44
Post-Modification Recorded Balance	$ 45		$ 45
Number of Loans	2		2