Note 14 - Employee Benefit Plans (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
The U.K. Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 0.6	$ 0.7	$ 0.6
Defined Contribution Plan Minimum Annual Contributions per Employee, Percent	5.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	5.00%
US Plan [Member]
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 0.2