Note 9 - Income Taxes (Details Textual)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	35.00%	35.00%
Effective Income Tax Rate Reconciliation, Percent	41.10%	41.60%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	4.40%	4.30%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent	1.90%	1.00%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent	(0.20%)	1.60%
Effective Income Tax Rate Reconciliation, Tax Contingency, State and Local, Percent		(0.30%)