Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
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Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Deferred Revenue Arrangement [Line Items] | |||
| Advertising expense | $ 226,969 | $ 206,351 | $ 203,945 |
| Research and development expense | $ 69,025 | $ 54,933 | $ 54,109 |
| Minimum | |||
| Deferred Revenue Arrangement [Line Items] | |||
| Length of prepaid subscriptions, term | 3 months | ||
| Maximum | |||
| Deferred Revenue Arrangement [Line Items] | |||
| Length of prepaid subscriptions, term | 12 months | ||
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- Definition Length of prepaid subscriptions term. No definition available.
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- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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- Definition The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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