Revenues - Disaggregation of Revenues (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation Of Revenue [Line Items]
Revenues		$ 6,796	$ 11,728	$ 22,731	$ 37,652
Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Revenues		4,383	8,696	15,654	28,548
Strategic Agreements [Member]
Disaggregation Of Revenue [Line Items]
Revenues		2,413	3,032	7,077	9,104
United States of America [Member]
Disaggregation Of Revenue [Line Items]
Revenues		5,051	8,802	17,133	28,135
United Kingdom [Member]
Disaggregation Of Revenue [Line Items]
Revenues		898	1,312	2,802	4,340
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues	[1]	$ 847	$ 1,614	$ 2,796	$ 5,177

[1] No individual country within the “Other” category accounted for 10% or more of revenues, net for any period presented.