Segment Information - By Reportable Segment (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment			2
Segment Reporting Information [Line Items]
Net sales	$ 319.3	$ 290.2	$ 934.8	$ 874.7
Operating income (loss)	18.0	3.1	52.1	11.6
Reportable Segments | IPG
Segment Reporting Information [Line Items]
Net sales	204.4	187.4	597.3	539.8
Operating income (loss)	19.8	8.3	55.2	24.8
Reportable Segments | ETG
Segment Reporting Information [Line Items]
Net sales	114.9	101.9	337.5	332.1
Operating income (loss)	5.3	0.1	16.8	6.7
Reportable Segments | NATG
Segment Reporting Information [Line Items]
Operating income (loss)	(0.3)	0.0	(0.7)	(2.4)
Corporate and Other
Segment Reporting Information [Line Items]
Net sales	0.0	0.9	0.0	2.8
Operating income (loss)	$ (6.8)	$ (5.3)	$ (19.2)	$ (17.5)