Share-Based Compensation - Unrecognized Compensation Expense (Detail) - Jun. 30, 2015 - USD ($) $ in Thousands	Total
Unrecognized Share Based Compensation Expense [Line Items]
Unrecognized Expense	$ 61,341
Stock options
Unrecognized Share Based Compensation Expense [Line Items]
Unrecognized Expense	$ 14,464
Average Expected Recognition Period - in Years	2 years 7 months 17 days
Restricted stock units
Unrecognized Share Based Compensation Expense [Line Items]
Unrecognized Expense	$ 46,877
Average Expected Recognition Period - in Years	2 years 9 months 22 days