Note 3 - Loans (Detail) - Average Recorded Investment and Income Recognized on Impaired Loans (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Average Recorded Investment	$ 31,476	$ 39,170
Interest Income Recognized	605	588
Commercial and Industrial [Member] | Period End Loans No Allocated Allowance For Loan Losses [Member]
Average Recorded Investment	1,117	3,931
Interest Income Recognized	54	72
Commercial and Industrial [Member] | Allocated Allowance [Member]
Average Recorded Investment	1,520	615
Interest Income Recognized	16	13
Commercial and Industrial [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	2,637	4,546
Interest Income Recognized	70	85
Commercial Real Estate Loans [Member] | Period End Loans No Allocated Allowance For Loan Losses [Member]
Average Recorded Investment	8,939	11,667
Interest Income Recognized	250	318
Commercial Real Estate Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	8,341	12,118
Interest Income Recognized	122	51
Commercial Real Estate Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	17,280	23,785
Interest Income Recognized	372	369
First Lien Residential Mortgage Loans [Member] | Period End Loans No Allocated Allowance For Loan Losses [Member]
Average Recorded Investment	0	0
Interest Income Recognized	0	0
First Lien Residential Mortgage Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	10,534	10,047
Interest Income Recognized	152	123
First Lien Residential Mortgage Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	10,534	10,047
Interest Income Recognized	152	123
Junior Lein Residential Mortgage Loans [Member] | Period End Loans No Allocated Allowance For Loan Losses [Member]
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Junior Lein Residential Mortgage Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	606	444
Interest Income Recognized	4	3
Junior Lein Residential Mortgage Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	606	444
Interest Income Recognized	4	3
Consumer Loans [Member] | Period End Loans No Allocated Allowance For Loan Losses [Member]
Average Recorded Investment	0	0
Interest Income Recognized	0	0
Consumer Loans [Member] | Allocated Allowance [Member]
Average Recorded Investment	419	348
Interest Income Recognized	7	8
Consumer Loans [Member] | Average Recorded Investment and Income Recognized [Member]
Average Recorded Investment	419	348
Interest Income Recognized	7	8
Period End Loans No Allocated Allowance For Loan Losses [Member]
Average Recorded Investment	10,056	15,598
Interest Income Recognized	304	390
Allocated Allowance [Member]
Average Recorded Investment	21,420	23,572
Interest Income Recognized	$ 301	$ 198