Balance Sheet Components - Schedule of Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Payables And Accruals [Abstract]
Accounts payable	$ 10,214	$ 7,448
Accrued inventory (in-transit and unvouchered receipts) and trade payables	7,570	3,548
Accrued purchasing card liability	2,000	1,581
Accrued franchise and use taxes	32	45
Other accrued expenses	894	245
Accounts payable and accrued expenses	$ 20,710	$ 12,867