Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Stock-based compensation expense
Increase in cash provided by operating activities over prior period			$ 1,100,000
Costs and expenses:
Total share-based compensation	970,000	707,000	2,627,000	1,832,000
Income tax benefit	(300,000)	(200,000)	(800,000)	(600,000)
Cost of revenue [Member]
Costs and expenses:
Total share-based compensation	105,000	90,000	283,000	253,000
Research and development costs [Member]
Costs and expenses:
Total share-based compensation	113,000	100,000	293,000	231,000
Selling, general and administrative [Member]
Costs and expenses:
Total share-based compensation	$ 752,000	$ 517,000	$ 2,051,000	$ 1,348,000