Note 4 - Loans and Leases - Internally Assigned Risk Grades of Loans (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Loans		$ 2,525,709	$ 2,548,171
Commercial and Industrial Portfolio Segment [Member]
Loans		827,747	833,524
Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans	[1]	216,115	225,050
Undevelopment Land Portfolio Segment [Member]
Loans		28,433	30,092
Real Estate Mortgage Portfolio Segment [Member]
Loans		1,408,151	1,411,447
Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		586,648	588,610
Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		428,163	426,373
Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		277,847	276,017
Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		48,656	49,500
Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		66,837	70,947
Consumer Portfolio Segment [Member]
Loans		45,263	48,058
Pass [Member]
Loans		2,460,657	2,493,020
Pass [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans		791,469	803,073
Pass [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans		216,115	220,532
Pass [Member] | Undevelopment Land Portfolio Segment [Member]
Loans		28,433	29,618
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member]
Loans		1,379,377	1,391,739
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		580,591	586,543
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		408,777	411,722
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		275,293	273,537
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans		48,587	49,500
Pass [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		66,129	70,437
Pass [Member] | Consumer Portfolio Segment [Member]
Loans		45,263	48,058
Special Mention [Member]
Loans		34,983	28,354
Special Mention [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans		18,453	11,516
Special Mention [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans			4,200
Special Mention [Member] | Undevelopment Land Portfolio Segment [Member]
Loans
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member]
Loans		16,530	12,638
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans		1,145	1,815
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans		13,628	9,030
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans		1,522	1,544
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans
Special Mention [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans		235	249
Special Mention [Member] | Consumer Portfolio Segment [Member]
Loans
Substandard [Member] | Performing Financial Instruments [Member]
Loans		26,303	23,399
Substandard [Member] | Nonperforming Financial Instruments [Member]
Loans		3,766	3,398
Substandard [Member] | Commercial and Industrial Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		17,607	18,703
Substandard [Member] | Commercial and Industrial Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		218	232
Substandard [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans
Substandard [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans			318
Substandard [Member] | Undevelopment Land Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans
Substandard [Member] | Undevelopment Land Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans			474
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans		8,696	4,696
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Commercial Investment [Member]
Loans		4,224	15
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Owner Occupied Commercial [Member]
Loans		4,292	4,500
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | One to Four Family Residential [Member]
Loans		161	162
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Home Equity First Lien [Member]
Loans
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Performing Financial Instruments [Member] | Home Equity Junior Lien [Member]
Loans		19	19
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans		3,548	2,374
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Commercial Investment [Member]
Loans		688	237
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Owner Occupied Commercial [Member]
Loans		1,466	1,121
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | One to Four Family Residential [Member]
Loans		871	774
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Home Equity First Lien [Member]
Loans		69
Substandard [Member] | Real Estate Mortgage Portfolio Segment [Member] | Nonperforming Financial Instruments [Member] | Home Equity Junior Lien [Member]
Loans		454	242
Substandard [Member] | Consumer Portfolio Segment [Member] | Performing Financial Instruments [Member]
Loans
Substandard [Member] | Consumer Portfolio Segment [Member] | Nonperforming Financial Instruments [Member]
Loans
Doubtful [Member]
Loans
Doubtful [Member] | Commercial and Industrial Portfolio Segment [Member]
Loans
Doubtful [Member] | Construction and Development Excluding Undeveloped Land Portfolio Segment [Member]
Loans
Doubtful [Member] | Undevelopment Land Portfolio Segment [Member]
Loans
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member]
Loans
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Commercial Investment [Member]
Loans
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Owner Occupied Commercial [Member]
Loans
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | One to Four Family Residential [Member]
Loans
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity First Lien [Member]
Loans
Doubtful [Member] | Real Estate Mortgage Portfolio Segment [Member] | Home Equity Junior Lien [Member]
Loans
Doubtful [Member] | Consumer Portfolio Segment [Member]
Loans

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