Note 4 - Loans and Leases - Internally Assigned Risk Grades of Loans (Details) - USD ($) $ in Thousands		Sep. 30, 2019	Dec. 31, 2018
Loans	[1]	$ 2,856,664	$ 2,548,171
Commercial and Industrial Portfolio Segment [Member]
Loans		876,127	833,524
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans	[2]	248,296	225,050
Undevelopment Land Portfolio Segment [Member]
Loans		35,169	30,092
Real Estate Mortgage Portfolio Segment [Member]
Loans		1,653,504	1,411,447
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		727,531	588,610
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		470,678	426,373
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		331,747	276,017
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		51,015	49,500
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		72,533	70,947
Consumer Portfolio Segment [Member]
Loans		43,568	48,058
Pass [Member]
Loans		2,789,805	2,493,020
Pass [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans		838,507	803,073
Pass [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans		248,296	220,532
Pass [Member] | Undevelopment Land Portfolio Segment [Member]
Loans		35,169	29,618
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member]
Loans		1,624,265	1,391,739
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		715,432	586,543
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		456,106	411,722
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		329,678	273,537
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		51,015	49,500
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		72,034	70,437
Pass [Member] | Consumer Portfolio Segment [Member]
Loans		43,568	48,058
Special Mention [Member]
Loans		24,487	28,354
Special Mention [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans		13,924	11,516
Special Mention [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans		0	4,200
Special Mention [Member] | Undevelopment Land Portfolio Segment [Member]
Loans		0	0
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member]
Loans		10,563	12,638
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		1,835	1,815
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		6,825	9,030
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		1,690	1,544
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		0	0
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		213	249
Special Mention [Member] | Consumer Portfolio Segment [Member]
Loans		0	0
Substandard [Member] | Performing Financial Instruments [Member]
Loans		38,691	23,399
Substandard [Member] | Nonperforming Financial Instruments [Member]
Loans		3,681	3,398
Substandard [Member] | Commercial and Industrial Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		23,488	18,703
Substandard [Member] | Commercial and Industrial Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		208	232
Substandard [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		0	0
Substandard [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		0	318
Substandard [Member] | Undevelopment Land Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		0	0
Substandard [Member] | Undevelopment Land Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		0	474
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		15,203	4,696
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Commercial Investment [Member]
Loans		8,690	15
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Owner Occupied Commercial [Member]
Loans		6,338	4,500
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | One to Four Family Residential [Member]
Loans		157	162
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Home Equity First Lien [Member]
Loans		0	0
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Home Equity Junior Lien [Member]
Loans		18	19
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		3,473	2,374
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Commercial Investment [Member]
Loans		1,574	237
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Owner Occupied Commercial [Member]
Loans		1,409	1,121
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | One to Four Family Residential [Member]
Loans		222	774
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Home Equity First Lien [Member]
Loans		0	0
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Home Equity Junior Lien [Member]
Loans		268	242
Substandard [Member] | Consumer Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		0	0
Substandard [Member] | Consumer Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		0	0
Doubtful [Member]
Loans		0	0
Doubtful [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans		0	0
Doubtful [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans		0	0
Doubtful [Member] | Undevelopment Land Portfolio Segment [Member]
Loans		0	0
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member]
Loans		0	0
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		0	0
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		0	0
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		0	0
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		0	0
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		0	0
Doubtful [Member] | Consumer Portfolio Segment [Member]
Loans		$ 0	$ 0

[1] Total loans are presented inclusive of premiums, discounts, and net loan origination fees and costs.

[2] Consists of land acquired for development by the borrower, but for which no development has yet taken place.