Stock-Based Compensation (Schedule Of Stock-Based Compensation Expense By Statement Of Operations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	$ 765	$ 418	$ 1,827	$ 1,013
Tax benefit	0	0	0	0
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, net of tax	765	418	1,827	1,013
Cost of service revenues
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	63	41	149	87
Cost of product revenues
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	0	0	1	0
Research and development
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	125	72	295	176
Sales and marketing
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	355	255	979	610
General and administrative
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	$ 222	$ 50	$ 403	$ 140