Note 12 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Income Tax Expense (Benefit)	$ 1,193	$ 926	$ 1,668	$ 1,270
Effective Income Tax Rate Reconciliation, Percent	7.40%	7.60%	5.40%	5.50%
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	$ 3,900		$ 3,900		$ 3,500
Unrecognized Tax Benefits	15,300		15,300		14,400
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 400		$ 400		$ 300