v3.7.0.1

Operating Segment and Geographic Information - Additional Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Apr. 30, 2017 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)	Jul. 31, 2016 USD ($)	Apr. 30, 2016 USD ($)	Jan. 31, 2016 USD ($)	Oct. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)	Apr. 30, 2017 USD ($)	Apr. 30, 2016 USD ($)	Apr. 30, 2015 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of Operating Segments									1
Number of Reportable Segments									1
Revenue	$ 50,209	$ 50,525	$ 50,408	$ 50,093	$ 50,709	$ 50,255	$ 49,926	$ 48,876	$ 201,235	$ 199,766	$ 191,181
UNITED KINGDOM
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									25,800	26,000	22,900
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue									$ 142,200	$ 140,800	$ 133,700

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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.

+ References

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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