Note 16 - Segment and Geographic Information - Total Revenue by Geographic Location (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Total Revenue	$ 33,462	$ 26,581	$ 56,848	$ 48,864
Percentage of Revenue	100.00%	100.00%	100.00%	100.00%
UNITED STATES
Total Revenue	$ 27,447	$ 21,895	$ 46,377	$ 39,906
Percentage of Revenue	82.00%	82.00%	82.00%	82.00%
Europe [Member]
Total Revenue	$ 4,060	$ 2,977	$ 6,889	$ 5,542
Percentage of Revenue	12.00%	11.00%	12.00%	11.00%
Other Location [Member]
Total Revenue	$ 1,955	$ 1,709	$ 3,582	$ 3,416
Percentage of Revenue	6.00%	7.00%	6.00%	7.00%