Note 8 - Equity Investment (Details Textual) - M W L [Member] - USD ($)	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Percentage Owned by Non-related Party [Member]
Equity Method Investment, Ownership Percentage	55.00%
Trade Accounts Receivable [Member]
Due from Affiliates	$ 268,000
Equity Method Investment, Ownership Percentage	45.00%
Revenue from Related Parties	$ 642,000	$ 2,000,000
Due to Affiliate	$ 4,000,000

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.

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