Loans and Leases, Part III (Details) (USD $)	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	$ 21,115,000		$ 22,834,000
Recorded Investment With No Allowance	11,268,000		13,452,000
Recorded Investment With Allowance	8,765,000		8,479,000
Total Recorded Investment	20,033,000		21,931,000
Related Allowance	610,000		658,000
Average recorded investment	20,984,000		27,039,000
Interest recognized	96,000	143,000	468,000
Interest income recognized on impaired loans	96,000	143,000	468,000
Commercial and Business Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,180,000		1,488,000
Recorded Investment With No Allowance	514,000		767,000
Recorded Investment With Allowance	519,000		576,000
Total Recorded Investment	1,033,000		1,343,000
Related Allowance	28,000		37,000
Average recorded investment	1,188,000		5,468,000
Interest recognized	3,000		26,000
Interest income recognized on impaired loans	3,000		26,000
Government Program Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	426,000		109,000
Recorded Investment With No Allowance	80,000		88,000
Recorded Investment With Allowance	0		0
Total Recorded Investment	80,000		88,000
Related Allowance	0		0
Average recorded investment	84,000		147,000
Interest recognized	0		0
Interest income recognized on impaired loans	0		0
Total Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,606,000		1,597,000
Recorded Investment With No Allowance	594,000		855,000
Recorded Investment With Allowance	519,000		576,000
Total Recorded Investment	1,113,000		1,431,000
Related Allowance	28,000		37,000
Average recorded investment	1,272,000		5,615,000
Interest recognized	3,000		26,000
Interest income recognized on impaired loans	3,000		26,000
Commercial Real Estate Term Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	10,455,000		11,393,000
Recorded Investment With No Allowance	6,002,000		6,818,000
Recorded Investment With Allowance	4,272,000		4,237,000
Total Recorded Investment	10,274,000		11,055,000
Related Allowance	411,000		436,000
Average recorded investment	10,665,000		8,498,000
Interest recognized	32,000		135,000
Interest income recognized on impaired loans	32,000		135,000
Residential Mortgages [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance			7,461,000
Recorded Investment With No Allowance			3,726,000
Recorded Investment With Allowance			3,666,000
Total Recorded Investment			7,392,000
Related Allowance			185,000
Average recorded investment			4,416,000
Interest recognized			251,000
Interest income recognized on impaired loans			251,000
Home Improvement and Home Equity Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	9,000		10,000
Recorded Investment With No Allowance	9,000		10,000
Recorded Investment With Allowance	0		0
Total Recorded Investment	9,000		10,000
Related Allowance	0		0
Average recorded investment	10,000		21,000
Interest recognized	0		0
Interest income recognized on impaired loans	0		0
Total Real Estate Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	17,456,000		18,864,000
Recorded Investment With No Allowance	8,954,000		10,554,000
Recorded Investment With Allowance	8,246,000		7,903,000
Total Recorded Investment	17,200,000		18,457,000
Related Allowance	582,000		621,000
Average recorded investment	17,830,000		12,935,000
Interest recognized	89,000		386,000
Interest income recognized on impaired loans	89,000		386,000
Total RE Construction and Development Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	1,413,000		1,730,000
Recorded Investment With No Allowance	1,413,000		1,730,000
Recorded Investment With Allowance	0		0
Total Recorded Investment	1,413,000		1,730,000
Related Allowance	0		0
Average recorded investment	1,572,000		7,298,000
Interest recognized	0		0
Interest income recognized on impaired loans	0		0
Total Agricultural Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	503,000		504,000
Recorded Investment With No Allowance	190,000		192,000
Recorded Investment With Allowance	0		0
Total Recorded Investment	190,000		192,000
Related Allowance	0		0
Average recorded investment	191,000		991,000
Interest recognized	3,000		0
Interest income recognized on impaired loans	3,000		0
Consumer Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	137,000		139,000
Recorded Investment With No Allowance	117,000		121,000
Recorded Investment With Allowance	0		0
Total Recorded Investment	117,000		121,000
Related Allowance	0		0
Average recorded investment	119,000		200,000
Interest recognized	1,000		6,000
Interest income recognized on impaired loans	1,000		6,000
Overdraft Protection Lines [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	0		0
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	0		0
Total Recorded Investment	0		0
Related Allowance	0		0
Average recorded investment	0		0
Interest recognized	0		0
Interest income recognized on impaired loans	0		0
Overdrafts [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	0		0
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	0		0
Total Recorded Investment	0		0
Related Allowance	0		0
Average recorded investment	0		0
Interest recognized	0		0
Interest income recognized on impaired loans	0		0
Single Family Residential Loans [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	6,992,000
Recorded Investment With No Allowance	2,943,000
Recorded Investment With Allowance	3,974,000
Total Recorded Investment	6,917,000
Related Allowance	171,000
Average recorded investment	7,155,000
Interest recognized	57,000
Interest income recognized on impaired loans	57,000
Total Installment/Other [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	137,000		139,000
Recorded Investment With No Allowance	117,000		121,000
Recorded Investment With Allowance	0		0
Total Recorded Investment	117,000		121,000
Related Allowance	0		0
Average recorded investment	119,000		200,000
Interest recognized	1,000		6,000
Interest income recognized on impaired loans	1,000		6,000
Commercial Lease Financing [Member]
Financing Receivable, Impaired [Line Items]
Unpaid Contractual Principal Balance	0		0
Recorded Investment With No Allowance	0		0
Recorded Investment With Allowance	0		0
Total Recorded Investment	0		0
Related Allowance	0		0
Average recorded investment	0		0
Interest recognized	0		0
Interest income recognized on impaired loans	$ 0		$ 0