Net Income Per Share (Calculations Of Basic And Diluted Net Income Per Share And Potential Common Shares) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011	Dec. 31, 2010
Net Income Per Share [Abstract]
Net income	$ 10,031	$ 11,101	$ 19,481	$ 26,494
Weighted average common shares outstanding	41,523	42,105	42,126	41,946
Basic net income per share	$ 0.24	$ 0.26	$ 0.46	$ 0.63
Weighted average stock options	141	310	157	333
Weighted average restricted stock units	639	758	532	557
Diluted weighted average shares	42,303	43,173	42,815	42,836
Diluted net income per share	$ 0.24	$ 0.26	$ 0.46	$ 0.62