Note 7 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Extended Maturity [Member] \| Commercial And Industrial [Member]
Number of contracts	2	2	3
Extended Maturity [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Number of contracts	1	1	2
Extended Maturity [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Number of contracts		1
Extended Maturity [Member] \| Real Estate Construction Porfolio Segment [Member]
Number of contracts			1
Extended Maturity [Member] \| Consumer Portfolio Segment [Member]
Number of contracts	1		1
Other Restructurings [Member] \| Commercial And Industrial [Member]
Number of contracts			1
Other Restructurings [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Number of contracts			1
Other Restructurings [Member] \| Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Number of contracts
Other Restructurings [Member] \| Real Estate Construction Porfolio Segment [Member]
Number of contracts
Other Restructurings [Member] \| Consumer Portfolio Segment [Member]
Number of contracts
Commercial And Industrial [Member]
Number of contracts	2	2	4
Pre-modification outstanding recorded investment	$ 15	$ 169	$ 126
Post-modification outstanding recorded investment	15	169	126
Post-modification outstanding recorded investment	$ 15	$ 169	$ 126
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
Number of contracts	1	1	3
Pre-modification outstanding recorded investment	$ 164	$ 58	$ 398
Post-modification outstanding recorded investment	164	58	418
Post-modification outstanding recorded investment	$ 164	$ 58	$ 418
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
Number of contracts		1
Pre-modification outstanding recorded investment		$ 311
Post-modification outstanding recorded investment		311
Post-modification outstanding recorded investment		$ 311
Real Estate Construction Porfolio Segment [Member]
Number of contracts			1
Pre-modification outstanding recorded investment			$ 181
Post-modification outstanding recorded investment
Post-modification outstanding recorded investment
Consumer Portfolio Segment [Member]
Number of contracts	1		1
Pre-modification outstanding recorded investment	$ 9		$ 9
Post-modification outstanding recorded investment	9		9
Post-modification outstanding recorded investment	$ 9		$ 9

Number of financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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