Note 4 - Loans and Allowance for Loan Losses - Concentrations Within the Loan Portfolio (Details) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Loans	$ 2,558,552,000	$ 2,378,620,000
Percent of portfolio	100.00%	100.00%
Commercial Real Estate Loans to Lessors of Non Residential Buildings [Member]
Loans	$ 547,841,000	$ 562,902,000
Percent of portfolio	21.40%	23.70%

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524

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