5. Securities (Summary Of Amortized Cost, Unrealized Gains, Unrealized Losses And Estimated Fair Values) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Available for sale securities, Amortized Cost	$ 289,822	$ 281,511	$ 273,684
Available for sale securities, Unrealized Gains	5,501	8,837	8,855
Available for sale securities, Unrealized Losses	4,143	1,197	1,000
Available for sale securities, Estimated Fair Value	291,180	289,151	281,539
U S Government Corporations And Agencies Securities [Member]
Available for sale securities, Amortized Cost	35,605	18,000	28,128
Available for sale securities, Unrealized Gains	1,186	665	892
Available for sale securities, Unrealized Losses	27	2	0
Available for sale securities, Estimated Fair Value	36,764	18,663	29,020
Government Sponsored Agencies [Member]
Available for sale securities, Amortized Cost	147,738	157,618	133,812
Available for sale securities, Unrealized Gains	2,313	3,846	3,250
Available for sale securities, Unrealized Losses	1,510	297	492
Available for sale securities, Estimated Fair Value	148,541	161,167	136,570
Nongovernment Sponsored Agencies [Member]
Available for sale securities, Amortized Cost	12,373	23,188	15,380
Available for sale securities, Unrealized Gains	326	550	509
Available for sale securities, Unrealized Losses	42	477	144
Available for sale securities, Estimated Fair Value	12,657	23,261	15,745
U S States And Political Subdivisions [Member]
Available for sale securities, Amortized Cost	13,838	8,672	12,187
Available for sale securities, Unrealized Gains	2	27	71
Available for sale securities, Unrealized Losses	493	43	89
Available for sale securities, Estimated Fair Value	13,347	8,656	12,169
Corporate Debt Securities [Member]
Available for sale securities, Amortized Cost	3,966	1,951	1,959
Available for sale securities, Unrealized Gains	27	16	29
Available for sale securities, Unrealized Losses	34	127	38
Available for sale securities, Estimated Fair Value	3,959	1,840	1,950
Taxable Debt Securities [Member]
Available for sale securities, Amortized Cost	213,520	209,429	191,466
Available for sale securities, Unrealized Gains	3,854	5,104	4,751
Available for sale securities, Unrealized Losses	2,106	946	763
Available for sale securities, Estimated Fair Value	215,268	213,587	195,454
Tax Exempt Debt Securities Us States And Political Subdivisions [Member]
Available for sale securities, Amortized Cost	76,225	69,036	79,403
Available for sale securities, Unrealized Gains	1,647	3,733	4,104
Available for sale securities, Unrealized Losses	2,037	251	237
Available for sale securities, Estimated Fair Value	75,835	72,518	83,270
Tax Exempt Debt Securities Residential Mortgage Backed Securities [Member]
Available for sale securities, Amortized Cost	0	2,969	2,738
Available for sale securities, Unrealized Gains	0	0	0
Available for sale securities, Unrealized Losses	0	0	0
Available for sale securities, Estimated Fair Value	0	2,969	2,738
Tax Exempt Debt Securities [Member]
Available for sale securities, Amortized Cost	76,225	72,005	82,141
Available for sale securities, Unrealized Gains	1,647	3,733	4,104
Available for sale securities, Unrealized Losses	2,037	251	237
Available for sale securities, Estimated Fair Value	75,835	75,487	86,008
Equity Securities [Member]
Available for sale securities, Amortized Cost	77	77	77
Available for sale securities, Unrealized Gains	0	0	0
Available for sale securities, Unrealized Losses	0	0	0
Available for sale securities, Estimated Fair Value	$ 77	$ 77	$ 77