Consolidated Statements of Operations (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Stock-based expense	$ 14,468	$ 22,453	$ 7,710
Cost of revenue
Stock-based expense	1,155	677	1,239
Selling and Marketing Expense
Stock-based expense	4,496	3,033	1,881
Research and Development Expense
Stock-based expense	2,817	2,840	1,335
General and Administrative Expense
Stock-based expense	$ 5,357	$ 4,608	$ 3,255