Operating Segment and Geographic Information - Revenue from Continuing Operations by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended									12 Months Ended
	Apr. 30, 2016	[1]	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 50,709		$ 50,255	$ 49,926	$ 48,876	$ 48,317	$ 49,562	$ 47,325	$ 45,977	$ 199,766	$ 191,181	$ 168,145
Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										150,758	146,086	127,766
EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										42,620	38,101	33,499
Other Geographic Area [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										$ 6,388	$ 6,994	$ 6,880

[1] During the fourth quarter of fiscal 2016, the Company recorded out of period adjustments related to errors in the timing of recognition of revenue, for which all required criteria had been satisfied in prior periods. The cumulative effect of out of period adjustments for the fourth quarter of fiscal 2016 was a $0.9 million increase in revenue. The Company has determined that these adjustments were not material to any prior annual or interim periods, and the resulting correction is not material to its annual results for fiscal 2016 or to the trend in earnings.