Note 3 - Loans (Detail) - Average Recorded Investment and Income Recognized on Impaired Loans (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Commercial and Industrial [Member] | No Allocated Allowance [Member]
Average Recorded Investment	$ 2,779	$ 2,647	$ 3,355	$ 1,502
Interest Income Recognized	18	35	164	37
Commercial and Industrial [Member] | Allocated Allowance [Member]
Average Recorded Investment	449	828	532	723
Interest Income Recognized	1	0	2	0
Commercial and Industrial [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	3,228	3,475	3,887	2,225
Interest Income Recognized	19	35	166	37
Commercial Real Estate Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	9,260	14,992	10,463	12,571
Interest Income Recognized	113	93	648	306
Commercial Real Estate Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	10,097	7,375	11,107	8,648
Interest Income Recognized	9	0	100	0
Commercial Real Estate Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	19,357	22,367	21,570	21,219
Interest Income Recognized	122	93	748	306
First Lien Residential Mortgage Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	9,451	8,874	9,749	9,009
Interest Income Recognized	56	83	295	234
First Lien Residential Mortgage Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
First Lien Residential Mortgage Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	9,451	8,874	9,749	9,009
Interest Income Recognized	56	83	295	234
Junior Lein Residential Mortgage Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	530	523	487	505
Interest Income Recognized	2	0	9	0
Junior Lein Residential Mortgage Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Junior Lein Residential Mortgage Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	530	523	487	505
Interest Income Recognized	2	0	9	0
Consumer Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	481	210	414	188
Interest Income Recognized	2	2	15	4
Consumer Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	0	0	0	0
Interest Income Recognized	0	0	0	0
Consumer Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	481	210	414	188
Interest Income Recognized	2	2	15	4
No Allocated Allowance [Member]
Average Recorded Investment	22,501	27,246	24,468	23,773
Interest Income Recognized	191	213	1,131	581
Allocated Allowance [Member]
Average Recorded Investment	10,546	8,203	11,639	9,371
Interest Income Recognized	10	0	102	0
Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	33,047	35,449	36,107	33,146
Interest Income Recognized	$ 201	$ 213	$ 1,233	$ 581