Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net sales to external customers:
Net sales	$ 703.8	$ 684.0
Segment EBIT:
Total EBIT for reportable segments	73.8	65.8
Unallocated corporate expenses	(12.9)	(10.5)
Continued Dumping & Subsidy Offset Act (CDSOA) receipts, net of expense	0.0	47.7
Interest expense	(7.9)	(8.4)
Investment Income, Interest	0.6	0.3
Income (Loss) Before Income Taxes	53.6	94.9
Mobile Industries [Member]
Net sales to external customers:
Net sales	383.0	383.2
Segment EBIT:
Total EBIT for reportable segments	30.8	32.0
Process Industries [Member]
Net sales to external customers:
Net sales	320.8	300.8
Segment EBIT:
Total EBIT for reportable segments	$ 43.0	$ 33.8