Share-based Compensation - Summary of RSU Activity (Parenthetical) (Detail)	9 Months Ended
Sep. 30, 2019
Restricted Stock Units (RSUs) [Member] \| Long Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
The target percentage of RSUs earned and vested	116.50%

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.

No definition available.

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