Assets (Details 3) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Accounts Receivable, Net
Allowance for doubtful accounts receivable (in dollars)	$ 500	$ 700
Prepaid expenses and other current assets
Supplier deposits	15,200	12,700
Inventories
Materials	33,378	28,637
Work in process	25,091	26,778
Finished goods	5,095	6,056
Inventories	$ 63,564	$ 61,471