| Goodwill - Reconciliation of Changes to Carrying Amount of Goodwill (Detail) - USD ($) $ in Thousands | 12 Months Ended | ||
|---|---|---|---|
| Mar. 31, 2017 | Mar. 31, 2016 | Mar. 31, 2015 | |
| Goodwill [Roll Forward] | |||
| Goodwill Beginning Balance | $ 76,621 | $ 76,747 | $ 4,837 | 
| Adjustments | 0 | (126) | 71,910 | 
| Goodwill Ending Balance | 76,621 | 76,621 | 76,747 | 
| Content | |||
| Goodwill [Roll Forward] | |||
| Goodwill Beginning Balance | 5,244 | 5,244 | 3,772 | 
| Adjustments | 0 | 0 | 1,472 | 
| Goodwill Ending Balance | 5,244 | 5,244 | 5,244 | 
| O&O | |||
| Goodwill [Roll Forward] | |||
| Goodwill Beginning Balance | 42,268 | 42,268 | 1,065 | 
| Adjustments | 0 | 0 | 41,203 | 
| Goodwill Ending Balance | 42,268 | 42,268 | 42,268 | 
| A&P | |||
| Goodwill [Roll Forward] | |||
| Goodwill Beginning Balance | 29,109 | 29,235 | 0 | 
| Adjustments | 0 | (126) | 29,235 | 
| Goodwill Ending Balance | $ 29,109 | $ 29,109 | $ 29,235 | 
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available. 
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