Credit Quality of Loans and Allowance for Loan Losses (Details 5) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012 Loan	Sep. 30, 2011 Loan	Sep. 30, 2012 Loan	Sep. 30, 2011 Loan
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts	3	5	6	22
Pre-modification outstanding recorded investment	$ 800	$ 1,145	$ 3,265	$ 5,072
Post-Modification outstanding recorded investment	800	1,145	3,265	5,007
Below Market Interest Rate [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts	1		2	3
Pre-modification outstanding recorded investment	533		2,476	1,397
Post-Modification outstanding recorded investment	533		2,476	1,397
Below Market Interest Rate [Member] | Real Estate Construction and Land Development [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts	1		1
Pre-modification outstanding recorded investment	533		533
Post-Modification outstanding recorded investment	533		533
Below Market Interest Rate [Member] | Real Estate Secured by Residential Properties [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts			1	1
Pre-modification outstanding recorded investment			1,943	219
Post-Modification outstanding recorded investment			1,943	219
Below Market Interest Rate [Member] | Real Estate Secured by Nonfarm Nonresidential [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts				1
Pre-modification outstanding recorded investment				1,145
Post-Modification outstanding recorded investment				1,145
Below Market Interest Rate [Member] | Credit Cards and Related Plans [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts				1
Pre-modification outstanding recorded investment				33
Post-Modification outstanding recorded investment				33
Extended Payment Terms [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts	2	5	4	9
Pre-modification outstanding recorded investment	267	1,145	789	2,750
Post-Modification outstanding recorded investment	267	1,145	789	2,750
Extended Payment Terms [Member] | Real Estate Construction and Land Development [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts	1		2	1
Pre-modification outstanding recorded investment	228		732	56
Post-Modification outstanding recorded investment	228		732	56
Extended Payment Terms [Member] | Real Estate Secured by Residential Properties [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts				3
Pre-modification outstanding recorded investment				1,549
Post-Modification outstanding recorded investment				1,549
Extended Payment Terms [Member] | Real Estate Secured by Nonfarm Nonresidential [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts		3		3
Pre-modification outstanding recorded investment		918		918
Post-Modification outstanding recorded investment		918		918
Extended Payment Terms [Member] | Commercial and Industrial [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts		2	1	2
Pre-modification outstanding recorded investment		227	18	227
Post-Modification outstanding recorded investment		227	18	227
Extended Payment Terms [Member] | Consumer Installment [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts	1		1
Pre-modification outstanding recorded investment	39		39
Post-Modification outstanding recorded investment	39		39
Forgiveness of Principal [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts				10
Pre-modification outstanding recorded investment				925
Post-Modification outstanding recorded investment				860
Forgiveness of Principal [Member] | Real Estate Construction and Land Development [Member]
Financing Receivable Breakdown of Types of Concessions Made by Loan Class
Financing Receivable, Modifications, Number of Contracts				10
Pre-modification outstanding recorded investment				925
Post-Modification outstanding recorded investment				$ 860