Summary of Other Current Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Prepaid Expense And Other Assets Current [Abstract]
Manufacturing-related deposits and prepaids	$ 23,604	$ 13,070
Other prepaids	2,377	3,109
Other	914	1,201
Total other current assets	$ 26,895	$ 17,380