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Stockholders' Equity - Summary of Restricted Stock, Restricted Stock Unit and Performance-based Stock Unit Activity (Parenthetical) (Detail) - Performance-Based Stock Units [Member] | 6 Months Ended
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Jun. 30, 2016 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Performance-based stock units, percentage of attainment level | 100.00%
Class A Common Stock [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Performance-based stock units | 43

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- Definition Additional shares of Class A Common Stock potentially issuable if maximum attainment levels are met. + References No definition available. + Details
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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. + References No definition available. + Details
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- Definition Percentage of vesting of share-based compensation awards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Details
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