v2.4.0.8

Discontinued Operations - Additional Information (Detail) (USD $) | 12 Months Ended |  | 0 Months Ended
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Apr. 30, 2014 | Jun. 04, 2014 Subsequent event | Jun. 12, 2012 PowerReviews
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Business acquisition total consideration |  |  | $ 150,754,000
Definitive agreement to divest PowerReviews, expected cash proceed |  | 30,000,000 |
Estimated pro forma loss on disposal of discontinued operations, net of taxes | $ (9,192,000) |  |

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