Geographic Information and Major Customer and Product Data - Revenues Within Geographical Areas (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
Revenue		$ 59,621	$ 62,190	$ 115,981	$ 115,718
North America
Segment Reporting Information [Line Items]
Revenue		39,984	38,441	77,833	70,061
EMEA
Segment Reporting Information [Line Items]
Revenue	[1]	17,553	21,481	33,952	41,828
Rest of World
Segment Reporting Information [Line Items]
Revenue		$ 2,084	$ 2,268	$ 4,196	$ 3,829

[1] Sales to customers in France accounted for $6,522 and $6,504 of the Company’s revenues for the three months ended June 30, 2019 and 2018, respectively. Sales to customers in the United Kingdom did not exceed 10% of total revenues for the three months ended June 30, 2019 and accounted for $7,111 of the Company’s revenues for the three months ended June 30, 2018. Sales to customers in France accounted for $12,763 and $13,259 of the Company’s revenues for the six months ended June 30, 2019 and 2018, respectively. Sales to customers in the United Kingdom did not exceed 10% of total revenues for the six months ended June 30, 2019 and accounted for $12,805 of the Company’s revenues for the six months ended June 30, 2018