Components of Loss Before Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Jan. 31, 2013	Oct. 31, 2012	Jul. 31, 2012	Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
U.S.									$ (55,508)	$ (50,538)	$ (24,711)
International									2,162	1,863	1,193
Loss from continuing operations before income taxes	$ (12,651)	$ (8,214)	$ (14,444)	$ (18,037)	$ (22,437)	$ (12,102)	$ (8,749)	$ (5,387)	$ (53,346)	$ (48,675)	$ (23,518)

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The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h)(1)(i))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 10

-Article 5

+ Details

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

+ References

+ Details

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