Stock-based Compensation Stock-Based Compensation Expense By Statement Of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	$ 3,517	$ 2,008	$ 6,539	$ 3,855
Tax benefit	0	0	0	0
Stock-based employee compensation expense related to employee stock options and employee stock purchases, net of tax	3,517	2,008	6,539	3,855
Cost of service revenue
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	263	160	482	275
Cost of product revenue
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	0	0	0	0
Research and development
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	726	315	1,257	629
Sales and marketing
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	1,422	910	2,619	1,654
General and administrative
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	$ 1,106	$ 623	$ 2,181	$ 1,297