Loans and Leases - Reserve for Loan and Lease Losses and Recorded Investment in Loans and Leases (Details 5) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010
Reserve for loan and lease losses:
Ending balance: individually evaluated for impairment	$ 432				$ 1,305
Ending balance: collectively evaluated for impairment	30,070				31,296
Total ending balance	30,502	30,597	29,870		32,601	32,804	30,898
Loans and leases:
Ending balance: individually evaluated for impairment	43,730				47,656
Ending balance: collectively evaluated for impairment	1,421,719				1,391,051
Total Loans and Leases	1,465,449		1,446,406	[1]	1,438,707
Commercial, financial and agricultural [Member]
Reserve for loan and lease losses:
Ending balance: individually evaluated for impairment	432				372
Ending balance: collectively evaluated for impairment	11,589				10,505
Total ending balance	12,021	11,701	11,262		10,877	11,098	9,630
Loans and leases:
Ending balance: individually evaluated for impairment	5,647				5,987
Ending balance: collectively evaluated for impairment	492,308				473,683
Total Loans and Leases	497,955				479,670
Real Estate - Commercial and Construction [Member]
Reserve for loan and lease losses:
Ending balance: individually evaluated for impairment					933
Ending balance: collectively evaluated for impairment	12,316				15,159
Total ending balance	12,316	13,352	13,317		16,092	16,464	15,288
Loans and leases:
Ending balance: individually evaluated for impairment	37,545				41,149
Ending balance: collectively evaluated for impairment	559,647				554,870
Total Loans and Leases	597,192				596,019
Real estate-residential secured for business purpose [Member]
Reserve for loan and lease losses:
Ending balance: collectively evaluated for impairment	834				1,019
Total ending balance	834	948	823		1,019	995	1,333
Loans and leases:
Ending balance: individually evaluated for impairment	177				218
Ending balance: collectively evaluated for impairment	31,920				32,499
Total Loans and Leases	32,097				32,717
Real Estate - Residential and Home Equity Secured for Personal Purpose [Member]
Reserve for loan and lease losses:
Ending balance: collectively evaluated for impairment	884				696
Total ending balance	884	732	735		696	594	544
Loans and leases:
Ending balance: individually evaluated for impairment	312				250
Ending balance: collectively evaluated for impairment	218,601				212,534
Total Loans and Leases	218,913				212,784
Loans to individuals [Member]
Reserve for loan and lease losses:
Ending balance: collectively evaluated for impairment	719				695
Total ending balance	719	704	730		695	701	734
Loans and leases:
Ending balance: individually evaluated for impairment	49				52
Ending balance: collectively evaluated for impairment	43,988				42,525
Total Loans and Leases	44,037				42,577
Lease Financings [Member]
Reserve for loan and lease losses:
Ending balance: collectively evaluated for impairment	1,161				1,912
Total ending balance	1,161	1,160	1,344		1,912	1,946	1,950
Loans and leases:
Ending balance: individually evaluated for impairment					0
Ending balance: collectively evaluated for impairment	75,255				74,940
Total Loans and Leases	75,255				74,940
Unallocated [Member]
Reserve for loan and lease losses:
Ending balance: collectively evaluated for impairment	2,567				1,310
Total ending balance	$ 2,567	$ 2,000	$ 1,659		$ 1,310	$ 1,006	$ 1,419

[1] Note: The consolidated balance sheet at December 31, 2011 has been derived from the audited financial statements at that date but does not include all of the information and footnotes required by U. S. generally accepted accounting principles for complete financial statements. Certain amounts have been reclassified to conform to the current-year presentation. See accompanying notes to the unaudited consolidated financial statements.