Note 3 - Loans (Details) - Recorded Investment In Loans By Credit Risk Profile (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Financing Receivable, Recorded Investment [Line Items]
Grade	$ 1,187,850	$ 1,103,478	$ 1,100,060
Commercial And Industrial [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	425,498	366,571
Commercial And Industrial [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	2,851	4,393
Commercial And Industrial [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	11,252	12,941
Commercial And Industrial [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	439,601	383,905	377,309
Real Estate Mortgage [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	673,267	611,159
Real Estate Mortgage [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	17,714	14,593
Real Estate Mortgage [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	44,299	76,728
Real Estate Mortgage [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Real Estate Mortgage [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	735,280	702,480	708,121
Real Estate Construction [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	8,607	5,163
Real Estate Construction [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Real Estate Construction [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	4,529
Real Estate Construction [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Real Estate Construction [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	8,607	9,692	7,907
Consumer And Other [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	4,362	7,401
Consumer And Other [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Consumer And Other [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Consumer And Other [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	0	0
Consumer And Other [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	4,362	7,401	6,723
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	1,111,734	990,294
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	20,565	18,986
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	55,551	94,198
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Grade	$ 0	$ 0