Summary of Significant Accounting Policies - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Costs and expenses:
Total share-based compensation	$ 4,135	$ 3,091	$ 7,251	$ 5,132
Income tax benefit	(1,016)	(1,144)	(1,769)	(1,860)
Decrease in net income	3,119	1,947	5,482	3,272
Cost of Revenue
Costs and expenses:
Total share-based compensation	348	290	581	427
Research and Development Costs
Costs and expenses:
Total share-based compensation	726	513	1,336	874
Selling, General and Administrative
Costs and expenses:
Total share-based compensation	$ 3,061	$ 2,288	$ 5,334	$ 3,831