Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Costs and expenses:
Total share-based compensation	$ 3,091	$ 1,918	$ 5,132	$ 3,177
Income tax benefit	(1,144)	(695)	(1,860)	(1,107)
Increase Decrease in Net Income	1,947	1,223	3,272	2,070
Cost of revenue [Member]
Costs and expenses:
Total share-based compensation	290	166	427	315
Research and development costs [Member]
Costs and expenses:
Total share-based compensation	513	334	874	417
Selling, general and administrative [Member]
Costs and expenses:
Total share-based compensation	$ 2,288	$ 1,418	$ 3,831	$ 2,445