Note 11 - Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income tax provision at U.S federal statutory rate	$ 44,638	$ 31,347	$ 15,927
State and local taxes, net of federal income tax benefit	(2,310)	(2,450)	(1,516)
Effect of foreign income taxed at rates other than the U.S. federal statutory rate	(1,154)	989	751
Foreign income inclusions		5,017	2,742
Tax credits	(200)	(4,685)	(2,692)
Tax audit settlements			(3,948)
Net change in valuation allowance	1,673	3,134	(25,169)
Domestic production deduction	(2,327)	(1,958)	(1,488)
Permanent items and other	(106)	995	2,766
Total Income Tax Expense/ (Benefit)	$ 40,214	$ 32,389	$ (12,627)