Loans and Allowance - Summary of Troubled Debt Restructurings by Modification (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Financing Receivable, Modifications [Line Items]
Modification	$ 1,766	$ 2,505	$ 4,271	$ 6,695
Troubled Debt Restructurings, Term Modifications
Financing Receivable, Modifications [Line Items]
Modification	1,732		1,785	2,451
Troubled Debt Restructurings Rate Modifications
Financing Receivable, Modifications [Line Items]
Modification	34	687	94	939
Troubled Debt Restructurings, Combination
Financing Receivable, Modifications [Line Items]
Modification		1,818	2,392	3,305
Commercial and industrial loans
Financing Receivable, Modifications [Line Items]
Modification	175	1,048	291	1,302
Commercial and industrial loans | Troubled Debt Restructurings, Term Modifications
Financing Receivable, Modifications [Line Items]
Modification	175		228	230
Commercial and industrial loans | Troubled Debt Restructurings Rate Modifications
Financing Receivable, Modifications [Line Items]
Modification
Commercial and industrial loans | Troubled Debt Restructurings, Combination
Financing Receivable, Modifications [Line Items]
Modification		1,048	63	1,072
Real estate loans - Construction
Financing Receivable, Modifications [Line Items]
Modification		299		639
Real estate loans - Construction | Troubled Debt Restructurings Rate Modifications
Financing Receivable, Modifications [Line Items]
Modification
Real estate loans - Construction | Troubled Debt Restructurings, Combination
Financing Receivable, Modifications [Line Items]
Modification		299		639
Real estate loans - Commercial and farm land
Financing Receivable, Modifications [Line Items]
Modification	1,399	875	3,349	2,758
Real estate loans - Commercial and farm land | Troubled Debt Restructurings, Term Modifications
Financing Receivable, Modifications [Line Items]
Modification	1,399		1,399	1,693
Real estate loans - Commercial and farm land | Troubled Debt Restructurings Rate Modifications
Financing Receivable, Modifications [Line Items]
Modification		680		680
Real estate loans - Commercial and farm land | Troubled Debt Restructurings, Combination
Financing Receivable, Modifications [Line Items]
Modification		195	1,950	385
Real estate loans - Residential
Financing Receivable, Modifications [Line Items]
Modification	192	167	605	1,880
Real estate loans - Residential | Troubled Debt Restructurings, Term Modifications
Financing Receivable, Modifications [Line Items]
Modification	158		158	528
Real estate loans - Residential | Troubled Debt Restructurings Rate Modifications
Financing Receivable, Modifications [Line Items]
Modification	34		94	252
Real estate loans - Residential | Troubled Debt Restructurings, Combination
Financing Receivable, Modifications [Line Items]
Modification		167	353	1,100
Individuals' loans for household and other personal expenditures
Financing Receivable, Modifications [Line Items]
Modification		116	26	116
Individuals' loans for household and other personal expenditures | Troubled Debt Restructurings Rate Modifications
Financing Receivable, Modifications [Line Items]
Modification		7		7
Individuals' loans for household and other personal expenditures | Troubled Debt Restructurings, Combination
Financing Receivable, Modifications [Line Items]
Modification		$ 109	$ 26	$ 109