Note 14 - Significant Customers / Concentration (Details Textual)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Customer Concentration Risk [Member] | Sales Revenue, Net [Member]
Number of Major Customers	4	4
Concentration Risk, Percentage	38.00%	67.00%
Customer Concentration Risk [Member] | Sales Revenue, Net [Member] | Major Customer 1 [Member]
Concentration Risk, Percentage	16.00%	33.00%
Customer Concentration Risk [Member] | Sales Revenue, Net [Member] | Major Customer 2 [Member]
Concentration Risk, Percentage	10.00%	25.00%
Customer Concentration Risk [Member] | Sales Revenue, Net [Member] | Major Customer 3 [Member]
Concentration Risk, Percentage	7.00%	5.00%
Customer Concentration Risk [Member] | Sales Revenue, Net [Member] | Major Customer 4 [Member]
Concentration Risk, Percentage	5.00%	4.00%
Geographic Concentration Risk [Member] | Assets, Total [Member] | DENMARK
Concentration Risk, Percentage	87.00%	85.00%
Geographic Concentration Risk [Member] | Assets, Total [Member] | UNITED STATES
Concentration Risk, Percentage	13.00%	15.00%