Note 9 - Allowance for Loan Losses and Credit Quality Information - Troubled Debt Restructurings that Subsequently Defaulted (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016 USD ($)	Jun. 30, 2015	Jun. 30, 2016 USD ($)	Jun. 30, 2015
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Number of Contracts that subsequently defaulted	1		1
Outstanding Recorded Investment	$ 183		$ 183
Commercial Portfolio Segment [Member] \| Commercial Real Estate Other [Member]
Number of Contracts that subsequently defaulted	1		1
Outstanding Recorded Investment	$ 44		$ 44
Number of Contracts that subsequently defaulted	2	0	2	0
Outstanding Recorded Investment	$ 227		$ 227

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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