Stock-based Compensation Stock-Based Compensation Expense By Statement Of Operations (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	$ 6,071	$ 4,663	$ 15,630	$ 11,202
Tax benefit	0	0	0	0
Stock-based employee compensation expense related to employee stock options and employee stock purchases, net of tax	6,071	4,663	15,630	11,202
Cost of service revenue
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	538	346	1,338	828
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	1,061	850	2,811	2,107
Sales and marketing
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	2,452	1,689	6,118	4,308
General and administrative
Stock-based employee compensation expense related to employee stock options and employee stock purchases, pre tax	$ 2,020	$ 1,778	$ 5,363	$ 3,959