Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Unearned compensation expense	$ 3.1
Estimated forfeiture rate	8.80%	11.00%

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration