Revenues - Revenues, Disaggregation of Revenues, Net (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018
Disaggregation Of Revenue [Line Items]
Revenues		$ 49,036	$ 58,631
Subscriptions [Member]
Disaggregation Of Revenue [Line Items]
Revenues		36,702	54,532
Strategic Agreements [Member]
Disaggregation Of Revenue [Line Items]
Revenues		12,334	4,099
United States of America [Member]
Disaggregation Of Revenue [Line Items]
Revenues		36,718	40,907
United Kingdom [Member]
Disaggregation Of Revenue [Line Items]
Revenues		5,489	7,664
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenues	[1]	$ 6,829	$ 10,060

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