Revenues, net - Contract Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Contract Acquisition Costs
Increase (Decrease) In Capitalized Contract Costs [Roll Forward]
Balance as of January 1	$ 713	$ 454
Addition	1,222	567
Amortization	(628)	(308)
Balance as of December 31	1,307	713
Contract Fulfillment Costs
Increase (Decrease) In Capitalized Contract Costs [Roll Forward]
Balance as of January 1	4,051	2,769
Addition	4,652	2,216
Amortization	(1,448)	(934)
Balance as of December 31	$ 7,255	$ 4,051