Revenues, Disaggregation of Revenues (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Abstract]
Revenues		$ 12,476	$ 14,251	$ 25,924	$ 29,653
Subscriptions [Member]
Disaggregation of Revenue [Abstract]
Revenues		9,427	13,897	19,853	28,912
Strategic Agreements [Member]
Disaggregation of Revenue [Abstract]
Revenues		3,049	354	6,071	741
United States of America [Member]
Disaggregation of Revenue [Abstract]
Revenues		9,292	9,584	19,333	19,795
United Kingdom [Member]
Disaggregation of Revenue [Abstract]
Revenues		1,483	2,012	3,028	4,122
Other [Member]
Disaggregation of Revenue [Abstract]
Revenues	[1]	$ 1,701	$ 2,655	$ 3,563	$ 5,736

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