Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Allocation of income tax expenses between current and deferred portions [Abstract]
Current	$ 5,064	$ 4,665	$ 3,660
Deferred (benefit) expense	181	582	563
Total income tax expense	5,245	5,247	4,223
Reconciliation of income tax expense [Abstract]
U.S. Federal income tax rate applied to income before income tax expense (in hundredths)	35.00%
Computed "expected" income tax expense	8,047	8,010	6,927
Tax-exempt interest income	(2,554)	(2,517)	(2,556)
Nondeductible interest expense	139	146	195
Other, net	(387)	(392)	(343)
Reported income tax expense	5,245	5,247	4,223
Deferred tax assets [Abstract]
Allowance for loan losses and unearned fee income	3,219	3,159
Valuation allowance on other real estate owned	73	210
Deferred compensation and other liabilities	2,176	1,788
Discount accretion of securities	19	0
Total deferred tax assets	5,487	5,157
Deferred tax liabilities [Abstract]
Fixed assets	(317)	(266)
Deposit intangibles	(1,039)	(912)
Other	(31)	(138)
Net unrealized gains on securities available for sale	(1,102)	(1,425)
Total deferred tax liabilities	(2,489)	(2,741)
Net deferred tax assets	$ 2,998	$ 2,416