Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid expenses	$ 10,276	$ 8,290
Sales taxes receivable from customers	0	120
Due from prior owners of acquired businesses for working capital settlements	916	1,021
Research and development tax credits receivable	375	898
Accrued interest receivable	372	0
Other	777	613
Total	$ 12,716	$ 10,942