Note 3 - Loans (Detail) - Average Recorded Investment and Income Recognized on Impaired Loans (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Commercial and Industrial [Member] | No Allocated Allowance [Member]
Average Recorded Investment	$ 3,582,000	$ 972,000	$ 3,840,000	$ 807,000
Interest Income Recognized	62,000	0	146,000	2,000
Commercial and Industrial [Member] | Allocated Allowance [Member]
Average Recorded Investment	348,000	836,000	556,000	788,000
Interest Income Recognized	0	0	1,000	0
Commercial and Industrial [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	3,930,000	1,808,000	4,397,000	1,595,000
Interest Income Recognized	62,000	0	147,000	2,000
Commercial Real Estate Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	9,854,000	11,716,000	10,549,000	11,191,000
Interest Income Recognized	217,000	11,000	535,000	208,000
Commercial Real Estate Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	10,662,000	8,623,000	11,790,000	8,990,000
Interest Income Recognized	40,000	0	91,000	5,000
Commercial Real Estate Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	20,516,000	20,339,000	22,339,000	20,181,000
Interest Income Recognized	257,000	11,000	626,000	213,000
First Lien Residential Mortgage Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	9,762,000	8,868,000	9,868,000	9,034,000
Interest Income Recognized	116,000	15,000	239,000	21,000
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	9,762,000	8,868,000	9,868,000	9,034,000
Interest Income Recognized	116,000	15,000	239,000	21,000
Junior Lein Residential Mortgage Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	530,000	451,000	446,000	486,000
Interest Income Recognized	4,000	0	7,000	130,000
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	530,000	451,000	446,000	486,000
Interest Income Recognized	4,000	0	7,000	130,000
Consumer Loans [Member] | No Allocated Allowance [Member]
Average Recorded Investment	501,000	190,000	404,000	171,000
Interest Income Recognized	5,000	2,000	13,000	2,000
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	501,000	190,000	404,000	171,000
Interest Income Recognized	5,000	2,000	13,000	2,000
No Allocated Allowance [Member]
Average Recorded Investment	24,229,000	22,196,000	25,107,000	21,688,000
Interest Income Recognized	404,000	28,000	940,000	363,000
Allocated Allowance [Member]
Average Recorded Investment	11,010,000	9,459,000	12,346,000	9,778,000
Interest Income Recognized	40,000	0	92,000	5,000
Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	35,239,000	31,655,000	37,453,000	31,466,000
Interest Income Recognized	$ 444,000	$ 28,000	$ 1,032	$ 368,000