Management Actions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended	12 Months Ended
	Dec. 31, 2017	Mar. 31, 2017	Sep. 30, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Approximate time anticipated savings will offset the restructuring charge	1 year	1 year
Restructuring Reserve [Roll Forward]
Restructuring Charges, net of noncash expenses				$ 9,558
Restructuring Reserve beginning balance			$ 3,436
Cash Payments			(1,694)	(6,312)
Foreign currency adjustments			(64)	190
Restructuring Reserve ending balance	$ 3,436		$ 1,678	$ 3,436
Selling and Administrative Expense
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 2,501	$ 8,018
Other associated restructuring charges		$ 961