Note 3 - Income Taxes - Discrete Tax Items (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2018
Tax-deductible IPO costs	$ (65)	$ (546)
Share based compensation tax deduction in excess of book expense	18	(723)
Reductions to unrecognized tax benefits and related interest	(3,344)	(3,344)
Transition tax estimate update	$ 716	$ 716

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