Note 3 - Loans (Details) - Internally Assigned Risk Grades of Loans - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 1,954,425	$ 1,868,550
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,904,566	1,814,936
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	32,797	24,800
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Performing Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	5,865	16,934
Nonperforming Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	11,197	11,880
Commercial and Industrial Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	610,877	571,754
Commercial and Industrial Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	591,923	546,582
Commercial and Industrial Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	9,946	6,215
Commercial and Industrial Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Commercial and Industrial Portfolio Segment [Member] | Performing Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	2,230	11,717
Commercial and Industrial Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	6,778	7,240
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	109,870	95,733
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	106,558	88,389
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	2,945	4,867
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Performing Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	341	1,720
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	26	757
Undevelopment Land Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	18,950	21,268
Undevelopment Land Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	18,273	20,578
Undevelopment Land Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	520	530
Undevelopment Land Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Undevelopment Land Portfolio Segment [Member] | Performing Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	157	160
Undevelopment Land Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,183,602	1,150,399
Real Estate Mortgage Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,156,771	1,130,143
Real Estate Mortgage Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	19,386	13,112
Real Estate Mortgage Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	491,171	487,822
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	484,638	482,415
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	5,755	4,991
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	357,628	340,982
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	340,032	328,385
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	12,038	6,942
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	222,643	211,548
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	220,287	209,396
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,496	1,129
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	49,937	43,779
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	49,846	43,765
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	62,223	66,268
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	61,968	66,182
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	97	50
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	3,137	3,337
Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Commercial Investment [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	493	181
Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Owner Occupied Commercial [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	2,523	3,156
Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | One to Four Family Residential [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Home Equity First Lien [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Home Equity Junior Lien [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	121	0
Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	4,308	3,807
Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Commercial Investment [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	285	235
Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Owner Occupied Commercial [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	3,035	2,499
Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | One to Four Family Residential [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	860	1,023
Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Home Equity First Lien [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	91	14
Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Home Equity Junior Lien [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	37	36
Consumer Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	31,126	29,396
Consumer Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	31,041	29,244
Consumer Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	76
Consumer Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Consumer Portfolio Segment [Member] | Performing Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	0	0
Consumer Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 85	$ 76