Restructuring Activities (Details) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) Position	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Restructuring Activities [Abstract]
Restructuring and related cost, expected number of positions eliminated | Position			40
Expected restructuring costs	$ 2,200		$ 2,200
Restructuring cost, cost incurred to date	2,000		2,000
Restructuring charges	$ 2	$ 190	2	$ 1,107	$ 1,300
Cumulative translation adjustment			1,300
Tax benefit			1,000
Payments			$ 54