Stock-Based Compensation (Schedule Of Stock-Based Compensation Expense By Statement Of Operations) (Details) (USD $)	3 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	$ 556,000	$ 266,000
Tax benefit	0	0
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, net of tax	556,000	266,000
Cost of service revenues
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	43,000	20,000
Cost of product revenues
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	1,000	0
Research and development
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	95,000	48,000
Sales and marketing
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	316,000	156,000
General and administrative
Stock-based employee compensation expense related to employee stock options and emolyee stock purchases, pre tax	$ 101,000	$ 42,000