Revenues, net - Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at the beginning of the period	$ 1,346	$ 1,255	$ 1,163	$ 956	$ 956
Additions during the period, net	186	(33)	381	265	354
Charged against allowance	(100)	(53)	(100)	(54)	(156)
Translation adjustment, if any	2	(1)	(10)	1	9
Balance at the end of the period	$ 1,434	$ 1,168	$ 1,434	$ 1,168	$ 1,163