Summary of Other Current Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Prepaid Expense and Other Assets, Current [Abstract]
Manufacturing-related deposits	$ 19,550	$ 30,668
Prepaid expenses	3,086	2,797
Other	455	1,571
Total other current assets	$ 23,091	$ 35,036