Stockholders' Equity - Additional Information (Detail) - shares |
3 Months Ended | |
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Mar. 31, 2018 |
Mar. 31, 2017 |
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| Class B Common Stock [Member] | ||
| Class of Stock [Line Items] | ||
| Certain Class B stockholders converted into Class A | 381,876 | 0 |
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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 number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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