Note 9 - Compensation Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Compensation expense (in millions)	$ 1.8	$ 1.9	$ 1.4
Total discretionary contribution (in millions)	$ 2.2	$ 2.4	$ 2.1
Guaranteed annual return	5.25%	5.25%	5.25%