Note 5 - Summary of Warranties (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Beginning Balance	$ 1,819	$ 1,203	$ 1,819	$ 1,167
Add: Accruals for warranties issued during the period	1,178	736	2,432	1,552
Less: Settlements made during the period	(997)	(685)	(2,251)	(1,465)
Ending Balance	$ 2,000	$ 1,254	$ 2,000	$ 1,254