Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Liabilities Disclosure [Abstract]
Accrued compensation and benefits	$ 17,348	$ 9,647
Accrued warranty	4,835	3,142	$ 3,335	$ 3,044
Accrued restructuring	440	1,371
Accrued professional services	1,469	1,237
Accrued contingent considerations	2,800	2,775
Customer deposits	3,634	1,164
Other	12,788	7,612
Total	$ 43,314	$ 26,948