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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Publisher FASB

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

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- Definition

The aggregate expense charged against earnings to allocate the cost of acquired intangible assets. As a noncash expense, this element is added back to net income when calculating cash provided by (used in) operations using the indirect method.

+ References

No definition available.

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- Definition

Amount of cash paid to acquire the entity.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

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-Publisher FASB

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-Number 141

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- Definition

Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

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-Publisher FASB

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

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- Definition

For an acquired entity, price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph e

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-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

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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.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

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-Publisher FASB

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-Paragraph 28

-Subparagraph (a)

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

+ References

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Business Combinations (Details Textual) (USD $) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended			3 Months Ended		3 Months Ended
	Jul. 31, 2012	Jul. 31, 2011	Apr. 30, 2012	Jul. 31, 2012 Power Reviews [Member]	Jun. 12, 2012 Power Reviews [Member]	Jul. 31, 2012 Power Reviews [Member] Common Stock
Business Combinations (Textual) [Abstract]
PowerReviews acquired in cash					$ 30,900,000
PowerReviews acquired in shares of common stock						6.4
Vested and unvested options of PowerReviews					1.7
Stock-based expense	12,338,000	1,558,000		9,800,000
Goodwill	112,700,000
Amortization of Acquired Intangible Assets	480,000			1,300,000
Acquisition costs				1,400,000
Consideration paid per share	$ 17.20
Stock based compensation related to post service combination service arrangements	$ 500,000