Note 11 - Purchase of Interests in Subsidiaries - Consolidated Statement of Income, Pro Forma (Details) - Brazil Acquisition [Member] - USD ($)	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business combination, pro forma information, revenue of acquiree since acquisition date, actual	$ 9,900,000	$ 33,838,000
Business combination, pro forma information, earnings or loss of acquiree since acquisition date, actual	$ 22,000	$ (266,000)

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration