Restructuring and Impairment Activities (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense	$ 1,600,000	$ 400,000	$ 2,000,000.0	$ 1,400,000
Restructuring Reserve [Roll Forward]
Balance at beginning of year			1,400,000	1,700,000	$ 1,700,000
Accruals for announced programs			2,000,000.0		1,300,000
Cash payments			(2,700,000)		(3,300,000)
Other			0		1,800,000
Exchange rate impacts			(100,000)		(100,000)
Balance at end of period	600,000		600,000		$ 1,400,000
AMS
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense	0.0	400,000	0.0	1,200,000
AMS | UNITED STATES | Asset Impairment Charge
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense				300,000
AMS | UNITED STATES | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense				900,000
EP
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense	$ 1,600,000	$ 0.0	2,000,000.0	200,000
EP | France and United States | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense				200,000
EP | Philippines | Asset Impairment Charge
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense			0	$ 0
EP | FRANCE | Employee Severance
Restructuring Cost and Reserve [Line Items]
Restructuring and impairment expense			$ 2,000,000.0