Note 10 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member] | Earliest Tax Year [Member]
Open Tax Year	2012
State and Local Jurisdiction [Member] | California Franchise Tax Board [Member] | Earliest Tax Year [Member]
Open Tax Year	2008
Income Tax Expense (Benefit)	$ 12,273	$ 9,738	$ 34,948	$ 31,102
Effective Income Tax Rate Reconciliation, Percent			30.10%	27.70%
Income Taxes Receivable					$ 28,900