Note 7 - Stock-based Compensation - Stock-based Compensation Expense and Related Income Tax Benefit (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Stock-based compensation expense, gross	$ 1,742	$ 1,434	$ 3,899	$ 2,772
Forfeitures	(528)		(528)
Income tax benefit at our statutory rate associated with stock-based compensation	(308)	(559)	(856)	(1,081)
Stock-based compensation expense, net	$ 906	$ 875	$ 2,515	$ 1,691

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Value of stock related to Restricted Stock Awards forfeited during the period.

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