Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Jul. 31, 2016	Jul. 31, 2015
Income Statement [Abstract]
Revenue	$ 50,093	$ 48,876
Cost of revenue	18,756	19,548
Gross profit	31,337	29,328
Operating expenses:
Sales and marketing	15,304	19,166
Research and development	11,073	10,533
General and administrative	8,259	8,238
Restructuring charges	327	0
Acquisition-related and other	176	702
Amortization of acquired intangible assets	309	309
Total operating expenses	35,448	38,948
Operating loss	(4,111)	(9,620)
Other income (expense), net:
Interest income	142	77
Interest expense	(489)	(571)
Other expense	(512)	(218)
Total other expense, net	(859)	(712)
Loss before income taxes	(4,970)	(10,332)
Income tax expense (benefit)	135	(88)
Net loss	$ (5,105)	$ (10,244)
Net loss per share:
Basic and diluted loss per share	$ (0.06)	$ (0.13)
Basic and diluted weighted average number of shares outstanding	82,214	80,174