Stock-Based Compensation - Summary of Stock Option Activity (Parenthetical) (Detail) - 2012 Stock Incentive Plan and 2012 Stock Option Plan [Member] - Chairman and Chief Executive Officer [Member]	May 02, 2017 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option to purchase of common stock \| shares	1,000,000
Exercise price of option granted \| $ / shares	$ 50

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.

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