Note 5 - Net Income per Share (Detail) - Net Income Per Share Basic And Diluted (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Net income (in Dollars)	$ 5,921	$ 5,473	$ 15,508	$ 10,848
Weighted average outstanding shares used to compute basic net income per share	35,145	33,594	34,677	34,149
Effect of dilutive securities	1,293	646	1,331	1,126
Weighted average outstanding shares used to compute diluted net income per share	36,438	34,240	36,008	35,275
Net income per share - basic (in Dollars per share)	$ 0.17	$ 0.16	$ 0.45	$ 0.32
Net income per share - diluted (in Dollars per share)	$ 0.16	$ 0.16	$ 0.43	$ 0.31