v3.5.0.1

Operating Segment and Geographic Information - Additional Information (Details) $ in Thousands	3 Months Ended									12 Months Ended
	Apr. 30, 2016 USD ($)	[1]	Jan. 31, 2016 USD ($)	Oct. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)	Apr. 30, 2015 USD ($)	Jan. 31, 2015 USD ($)	Oct. 31, 2014 USD ($)	Jul. 31, 2014 USD ($)	Apr. 30, 2016 USD ($)	Apr. 30, 2015 USD ($)	Apr. 30, 2014 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of Operating Segments										1
Number of Reportable Segments										1
Revenue	$ 50,709		$ 50,255	$ 49,926	$ 48,876	$ 48,317	$ 49,562	$ 47,325	$ 45,977	$ 199,766	$ 191,181	$ 168,145
UNITED KINGDOM
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										26,000	22,900	22,400
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue										$ 140,800	$ 133,700	$ 123,300
[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.

X

- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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