Summary of Significant Accounting Policies - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Costs and expenses:
Total share-based compensation	$ 5,437	$ 4,316	$ 10,830	$ 9,207
Income tax benefit	(1,305)	(1,102)	(2,569)	(2,317)
Decrease in net income	4,132	3,214	8,261	6,890
Cost of Revenue
Costs and expenses:
Total share-based compensation	589	536	1,013	999
Research and Development Costs
Costs and expenses:
Total share-based compensation	1,026	817	1,943	1,845
Selling, General and Administrative
Costs and expenses:
Total share-based compensation	$ 3,822	$ 2,963	$ 7,874	$ 6,363