Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Defined Benefit Plan, Actuarial Gain (Loss), Immediate Recognition as Component in Net Periodic Benefit (Cost) Credit	$ 2.4	$ 0.0	$ 2.4	$ (4.4)
Net sales to external customers:
Net sales	906.3	750.6	1,789.4	1,454.4
Segment EBIT:
Total EBIT for reportable segments	145.1	94.6	277.8	171.3
Unallocated corporate expenses	(15.2)	(12.9)	(29.5)	(24.3)
Interest expense	(10.7)	(8.5)	(20.7)	(16.4)
Investment Income, Interest	0.5	0.7	0.9	1.3
Income (Loss) Before Income Taxes	122.1	73.9	230.9	127.5
Mobile Industries [Member]
Net sales to external customers:
Net sales	489.1	408.4	977.6	791.4
Segment EBIT:
Total EBIT for reportable segments	54.5	34.4	105.6	67.0
Process Industries [Member]
Net sales to external customers:
Net sales	417.2	342.2	811.8	663.0
Segment EBIT:
Total EBIT for reportable segments	$ 90.6	$ 60.2	$ 172.2	$ 104.3