v3.5.0.1

Net Loss Per Share Applicable to Common Stockholders - Computations of Loss per Share Applicable to Common Stockholders (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended								12 Months Ended
		Apr. 30, 2016	Jan. 31, 2016	Oct. 31, 2015	Jul. 31, 2015	Apr. 30, 2015	Jan. 31, 2015	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Schedule Of Computation Of Basic And Diluted Earnings Per Common Share [Line Items]
Net loss from continuing operations		$ (7,129)	$ (3,114)	$ (4,852)	$ (10,244)	$ (8,825)	$ (4,123)	$ (9,908)	$ (10,308)	$ (25,339)	$ (33,164)	$ (52,846)
Net loss from discontinued operations, net of tax		0	0	0	0	0	0	0	(1,257)	0	(1,257)	(10,320)
Net loss applicable to common stockholders		$ (7,129)	$ (3,114)	$ (4,852)	$ (10,244)	$ (8,825)	$ (4,123)	$ (9,908)	$ (11,565)	$ (25,339)	$ (34,421)	$ (63,166)
Continuing operations		$ (0.09)	$ (0.04)	$ (0.06)	$ (0.13)	$ (0.11)	$ (0.05)	$ (0.13)	$ (0.13)	$ (0.31)	$ (0.42)	$ (0.70)
Discontinued operations		0.00	0.00	0.00	0.00	0.00	0.00	0.00	(0.02)	0.00	(0.02)	(0.14)
Basic and diluted loss per share:		$ (0.09)	$ (0.04)	$ (0.06)	$ (0.13)	$ (0.11)	$ (0.05)	$ (0.13)	$ (0.15)	$ (0.31)	$ (0.44)	$ (0.84)
Basic and diluted weighted average number of shares outstanding										80,859	78,645	75,564
Outstanding stock options
Potentially dilutive securities (1):
Outstanding stock options	[1]									197	721	2,149
Restricted shares
Potentially dilutive securities (1):
Outstanding stock options	[1]									49	427	293
[1] The impact of potentially dilutive securities on earnings per share is anti-dilutive in a period of net loss.

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Schedule Of Computation Of Basic And Diluted Earnings Per Common Share [Line Items]

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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 after tax of income (loss) from continuing operations attributable to the parent.

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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 after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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