Note 21 - Dividend Reinvestment Plan (Details Textual) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Issued During Period, Shares, Dividend Reinvestment Plan	69,084	65,044	72,231
Stock Issued During Period, Value, Dividend Reinvestment Plan	$ 2,822	$ 2,528	$ 2,277

Value of stock issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Name:	us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration