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Other stock related expense (benefit).

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Expiration Term

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Aggregate number of common shares reserved for future issuance.

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- Definition

Amounts due to employees, not to include stockholders or officers. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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-Subparagraph (SX 210.5-02.19(a))

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-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Subparagraph a

-Article 5

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

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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No definition available.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the plan.

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- Definition

The number of shares purchased on the open market during the period for issuance to employees under the plan.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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Stockholders Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase shares of common stock outstanding	5,093,000	7,091,000	10,829,000
Expected dividend yield assumed	0.00%
Share-based expense	$ 12,802	$ 14,468	$ 22,453
Weighted-average grant date fair value of options granted	$ 3.47	$ 4.32	$ 5.75
Aggregate intrinsic value of options exercised	$ 4,500	$ 18,600	$ 42,800
Aggregate fair value of options vested	0	0	0
Stock-based expense (benefit)	400
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based expense	4,677	$ 5,357	$ 4,608
Estimated liability for taxes, interest and related items	2,200
Loss from discontinued operations, net of tax
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Estimated liability for taxes, interest and related items	$ 800
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield assumed	0.00%	0.00%	0.00%
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Future period share-based expense period of recognition	3 years 15 days
Future period share-based expense	$ 23,600
Aggregate fair value of restricted stock shares vested	$ 6,200	$ 3,600	$ 1,000
2005 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase shares of common stock outstanding	1,718,468
Common shares reserved for Employee Stock Purchase Plan	1,718,468
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase shares of common stock outstanding	3,353,763
Common shares available for grant under Employee Stock Purchase Plan	6,787,141
2012 Equity Incentive Plan \| Vesting at end of one year
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option granted , vesting percentage	25.00%
2012 Equity Incentive Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of the fair market value of common stock	100.00%
2012 Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, maximum term	10 years
2012 Equity Incentive Plan \| Share Based Awards To More Than Ten Percent Owners \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of the fair market value of common stock	110.00%
2012 Equity Incentive Plan \| Share Based Awards To More Than Ten Percent Owners \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, maximum term	5 years
2012 Equity Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based award, vesting period	4 years
2012 Equity Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based award, vesting period	4 years
Restricted stock units outstanding	3,360,693
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price as a percentage of the fair market value of common stock	85.00%
Common stock share reserved to permit exercise of options outstanding	2,471,524
Number of common stock purchased by employees	441,144
Average price of common stock purchased by employees	$ 5.65
Employee Stock Purchase Plan \| Accrued Expenses and Other Current Liabilities
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount held on behalf of employees for future stock purchases	$ 400
2005 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized stock-based expense, adjusted for estimated forfeitures, related to stock options	$ 8,300
Future period share-based expense period of recognition	2 years 6 months 7 days
2005 Equity Incentive Plan \| PowerReviews
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase shares of common stock outstanding	20,824
Common stock share reserved to permit exercise of options outstanding	20,824