Net Loss Per Common Share - Additional Information (Detail) - $ / shares	Jun. 30, 2017	Jun. 30, 2016
Convertible Notes due 2018
Earnings Per Share [Line Items]
Debt instrument, interest rate, stated percentage, per annum	0.75%
Convertible Notes due 2020
Earnings Per Share [Line Items]
Debt instrument, interest rate, stated percentage, per annum	1.50%
The Notes
Earnings Per Share [Line Items]
Debt instrument, convertible, conversion price, per share	$ 94.15	$ 94.15