Note 8 - Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%	35.00%
Effective Income Tax Rate Reconciliation, Percent	38.80%	38.70%	42.60%	38.90%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Percent			2.70%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent			2.90%	4.60%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Percent			1.80%	0.50%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent			0.60%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent			0.40%	1.20%