Note 15 - Income Taxes - Summary of Income Tax Expense (Benefit) Charged to Statement of Comprehensive Income (Loss) and Statement of Stockholders' Equity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income tax expense	$ 2,584	$ 1,499	$ 10,200
Other comprehensive income (loss), tax effect	655	128	1,434
Excess tax expense (benefit) fromshare-based payments		$ 47	$ (733)