Restructuring Costs (Restructuring Liabilities) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Current period restructuring charges	$ 3,954	$ 877	$ 2,475
2016 Program
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	481	1,740
Current period restructuring charges	1,556	877	2,475
Cash payments	(2,031)	(2,055)
Foreign currency impact	(6)	(81)
Restructuring reserve ending balance	0	481	1,740
2016 Program | Severance costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	457	901
Current period restructuring charges	160	549	1,152
Cash payments	(615)	(954)
Foreign currency impact	(2)	(39)
Restructuring reserve ending balance	0	457	901
2016 Program | Lease termination costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	0	76
Current period restructuring charges	0	(4)	88
Cash payments	0	(70)
Foreign currency impact	0	(2)
Restructuring reserve ending balance	0	0	76
2016 Program | Other costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	24	763
Current period restructuring charges	1,396	332	1,235
Cash payments	(1,416)	(1,031)
Foreign currency impact	(4)	(40)
Restructuring reserve ending balance	0	24	$ 763
Other Restructuring Actions
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	0
Current period restructuring charges	2,398
Cash payments	(1,633)
Foreign currency impact	4
Restructuring reserve ending balance	761	0
Other Restructuring Actions | Severance costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	0
Current period restructuring charges	1,579
Cash payments	(858)
Foreign currency impact	(4)
Restructuring reserve ending balance	717	0
Other Restructuring Actions | Other costs
Restructuring Reserve [Roll Forward]
Restructuring reserve beginning balance	0
Current period restructuring charges	819
Cash payments	(775)
Foreign currency impact	0
Restructuring reserve ending balance	$ 44	$ 0