v2.4.0.8

Computations of Loss per Share Applicable to Common Stockholders (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Oct. 31, 2014		Oct. 31, 2013		Oct. 31, 2014		Oct. 31, 2013
Schedule Of Computation Of Basic And Diluted Earnings Per Common Share [Line Items]
Net loss from continuing operations	$ (9,908)		$ (14,574)		$ (20,216)		$ (32,220)
Net income (loss) from discontinued operations, net of tax			420		(1,257)		698
Net loss applicable to common stockholders	$ (9,908)		$ (14,154)		$ (21,473)		$ (31,522)
Continuing operations	$ (0.13)		$ (0.20)		$ (0.26)		$ (0.43)
Discontinued operations			$ 0.01		$ (0.02)		$ 0.01
Basic and diluted loss per share	$ (0.13)		$ (0.19)		$ (0.28)		$ (0.42)
Basic and diluted weighted average number of shares outstanding	78,280		75,088		78,023		74,535
Outstanding stock options
Potentially dilutive securities (1):
Outstanding stock options	813	[1]	2,757	[1]	864	[1]	2,933	[1]
Restricted Stock
Potentially dilutive securities (1):
Outstanding stock options	301	[1]	351	[1]	243	[1]	270	[1]
[1] The impact of potentially dilutive securities on earnings per share is anti-dilutive in a period of net loss.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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Amount of income (loss) from a disposal group, net of income tax before extraordinary items allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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