Operating Segment and Geographic Information - Revenue from Continuing Operations by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Apr. 30, 2017	Jan. 31, 2017	Oct. 31, 2016	Jul. 31, 2016	Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2017	Apr. 30, 2016	Apr. 30, 2015
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	$ 50,209	$ 50,525	$ 50,408	$ 50,093	$ 50,709	$ 50,255	$ 49,926	$ 48,876	$ 201,235	$ 199,766	$ 191,181
Americas [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									149,330	150,758	146,086
EMEA [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									44,529	42,620	38,101
Other Geographic Area [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									$ 7,376	$ 6,388	$ 6,994