Note 8 - Equity Investment (Details Textual) - M W L [Member] - USD ($)	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Percentage Owned by Non-related Party [Member]
Equity Method Investment, Ownership Percentage	55.00%
Trade Accounts Receivable [Member]
Due from Affiliates	$ 52,000
Equity Method Investment, Ownership Percentage	45.00%
Revenue from Related Parties	$ 966,000	$ 3,700,000
Due to Affiliate	$ 3,800,000

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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