Other Current Assets - Schedule of Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid expenses	$ 1,379	$ 2,186
Advances to vendors	6,727	1,806
Other receivables	139	1,343
Total	$ 8,245	$ 5,335