Geographic Information and Major Customer and Product Data - Revenues Within Geographical Areas (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenue		$ 65,649	$ 67,052	$ 181,630	$ 182,770
North America
Segment Reporting Information [Line Items]
Revenue		47,411	44,890	125,243	114,951
EMEA
Segment Reporting Information [Line Items]
Revenue	[1]	16,719	19,778	50,672	61,606
Rest of World
Segment Reporting Information [Line Items]
Revenue		$ 1,519	$ 2,384	$ 5,715	$ 6,213

[1] Sales to customers in France did not exceed 10% of total revenues for the nine months ended September 30, 2019 and accounted for $19,813 of the Company’s revenues for the nine months ended September 30, 2018. Sales to customers in the United Kingdom did not exceed 10% of total revenues for the nine months ended September 30, 2019 and accounted for $18,708 of the Company’s revenues for the nine months ended September 30, 2018.