Note 8 - Deposits - Interest Expense on Time Deposits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Interest bearing demand	$ 2,242	$ 1,740	$ 1,406
Money market accounts	15,062	13,308	10,138
Saving accounts	1,772	1,046	901
Time deposits	46,768	43,327	39,443
Total	$ 65,844	$ 59,421	$ 51,888

Aggregate amount of all interest expense on domestic deposit liabilities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Amount of interest expense on domestic demand deposit liabilities.

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Amount of interest expense on domestic money market demand account deposit liabilities.

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Amount of interest expense on domestic savings deposit liabilities.

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Amount of interest expense on time deposit liabilities.

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