Loans (Summary Of Impaired Loans) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Loans [Line Items]
Average Recorded Investment	$ 59,359	$ 81,722
Interest Income Recognized	473	1,982
Recorded Investment	53,525	65,186
Unpaid Principal Balance	61,239	72,651
Related Allowance	3,368	5,856
With No Related Allowance Recorded [Member] | Commercial [Member]
Loans [Line Items]
Average Recorded Investment	1,315	2,499
Interest Income Recognized	9	18
Recorded Investment	1,519	1,111
Unpaid Principal Balance	1,825	1,147
With No Related Allowance Recorded [Member] | Agriculture [Member]
Loans [Line Items]
Average Recorded Investment	72	463
Interest Income Recognized	2	7
Recorded Investment	34	109
Unpaid Principal Balance	34	109
With No Related Allowance Recorded [Member] | Consumer Installment Loans [Member]
Loans [Line Items]
Average Recorded Investment	95	83
Interest Income Recognized	2	10
Recorded Investment	92	98
Unpaid Principal Balance	92	98
With No Related Allowance Recorded [Member] | All Other Loans [Member]
Loans [Line Items]
Average Recorded Investment
Interest Income Recognized
Recorded Investment
Unpaid Principal Balance
Related Allowance
With No Related Allowance Recorded [Member] | Real Estate [Member] | Commercial [Member]
Loans [Line Items]
Average Recorded Investment	18,525	26,662
Interest Income Recognized	136	829
Recorded Investment	16,661	20,389
Unpaid Principal Balance	17,292	21,434
With No Related Allowance Recorded [Member] | Real Estate [Member] | Construction And Land Development [Member]
Loans [Line Items]
Average Recorded Investment	3,339	4,759
Interest Income Recognized	18	118
Recorded Investment	2,918	3,759
Unpaid Principal Balance	7,776	8,618
With No Related Allowance Recorded [Member] | Real Estate [Member] | Residential 1-4 Family [Member]
Loans [Line Items]
Average Recorded Investment	6,080	7,824
Interest Income Recognized	87	227
Recorded Investment	5,852	6,308
Unpaid Principal Balance	6,286	6,567
With No Related Allowance Recorded [Member] | Real Estate [Member] | Multifamily [Member]
Loans [Line Items]
Average Recorded Investment	1,063	1,021
Interest Income Recognized	22	44
Recorded Investment	1,198	928
Unpaid Principal Balance	1,268	998
With No Related Allowance Recorded [Member] | Real Estate [Member] | Farmland [Member]
Loans [Line Items]
Average Recorded Investment	3,832	7,748
Interest Income Recognized	16	168
Recorded Investment	3,289	4,375
Unpaid Principal Balance	3,756	4,810
With An Allowance Recorded [Member] | Commercial [Member]
Loans [Line Items]
Average Recorded Investment	1,117	1,689
Interest Income Recognized	(2)	19
Recorded Investment	353	1,881
Unpaid Principal Balance	455	1,885
Related Allowance	161	491
With An Allowance Recorded [Member] | Agriculture [Member]
Loans [Line Items]
Average Recorded Investment	239	373
Interest Income Recognized	3	3
Recorded Investment	125	353
Unpaid Principal Balance	125	353
Related Allowance	10	308
With An Allowance Recorded [Member] | Consumer Installment Loans [Member]
Loans [Line Items]
Average Recorded Investment	33	69
Interest Income Recognized	1	3
Recorded Investment	38	27
Unpaid Principal Balance	38	27
Related Allowance	16	16
With An Allowance Recorded [Member] | All Other Loans [Member]
Loans [Line Items]
Average Recorded Investment
Interest Income Recognized
Recorded Investment
Unpaid Principal Balance
Related Allowance
With An Allowance Recorded [Member] | Real Estate [Member] | Commercial [Member]
Loans [Line Items]
Average Recorded Investment	13,561	14,770
Interest Income Recognized	115	347
Recorded Investment	13,626	13,495
Unpaid Principal Balance	13,955	14,014
Related Allowance	2,583	3,196
With An Allowance Recorded [Member] | Real Estate [Member] | Construction And Land Development [Member]
Loans [Line Items]
Average Recorded Investment	533	1,728
Interest Income Recognized	9	41
Recorded Investment	272	793
Unpaid Principal Balance	394	945
Related Allowance	18	177
With An Allowance Recorded [Member] | Real Estate [Member] | Residential 1-4 Family [Member]
Loans [Line Items]
Average Recorded Investment	3,074	5,473
Interest Income Recognized	27	203
Recorded Investment	2,317	3,830
Unpaid Principal Balance	2,332	3,836
Related Allowance	337	577
With An Allowance Recorded [Member] | Real Estate [Member] | Multifamily [Member]
Loans [Line Items]
Average Recorded Investment	1,074	1,589
Interest Income Recognized	2	68
Recorded Investment	119	2,028
Unpaid Principal Balance	119	2,096
Related Allowance	12	456
With An Allowance Recorded [Member] | Real Estate [Member] | Farmland [Member]
Loans [Line Items]
Average Recorded Investment	5,407	4,972
Interest Income Recognized	26	(123)
Recorded Investment	5,112	5,702
Unpaid Principal Balance	5,492	5,714
Related Allowance	$ 231	$ 635