v2.4.0.8

Commitments and Contingencies - Additional Information (Detail) (USD $) | 0 Months Ended | 12 Months Ended |  | 0 Months Ended |
--- | --- | --- | --- | --- | ---
Mar. 12, 2013 | Apr. 30, 2014 | Apr. 30, 2013 | Apr. 30, 2012 | Jun. 04, 2014 Subsequent event | Jun. 12, 2012 PowerReviews | Apr. 30, 2014 Minimum | Apr. 30, 2014 Maximum
Commitments and Contingencies Disclosure [Line Items] |  |  |  |  |  |  |  |
Rental expense |  | $ 4,400,000 | $ 3,800,000 | $ 1,700,000 |  |  |  |
Shares of common Stock issued in business acquisition |  |  |  |  |  | 6,400,000 |  |
Business acquisition total consideration |  |  |  |  |  | 150,754,000 |  |
Number of vested and unvested options equivalent to the acquired company's option |  | 6,901,000 |  |  |  | 1,700,000 |  |
Definitive agreement to divest PowerReviews, expected cash proceed |  |  |  |  | 30,000,000 |  |  |
Estimated loss on disposal of discontinued operations, net of tax |  | (9,192,000) |  |  |  |  |  |
Damages sought in shareholder derivative action | 91,400,000 |  |  |  |  |  |  |
Sales tax liability estimate |  |  |  |  |  |  | 2,500,000 | 3,200,000
Sales tax liability accrual |  | $ 3,000,000 |  |  |  |  |  |

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- Definition Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479 + Details
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