Note 9 - Earnings Per Share (Details) - Dilutive effect of stock options, restricted stock, and RSU awards for each period (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Dilutive effect of stock options, restricted stock, and RSU awards for each period [Abstract]
Net Income (in Dollars)	$ 11,131	$ 9,573	$ 31,574	$ 28,856
Weighted-average number of basic shares outstanding during the period	19,802	19,610	19,685	19,717
Dilutive effect of stock options, restricted stock and RSUs	363	160	403	287
Weighted-average number of diluted shares outstanding during the period	20,165	19,770	20,088	20,004
Basic earnings per share (in Dollars per share)	$ 0.56	$ 0.49	$ 1.60	$ 1.46
Diluted earnings per share (in Dollars per share)	$ 0.55	$ 0.48	$ 1.57	$ 1.44