Segments (Schedule of Segment Information) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Net sales:
Net sales	$ 366.0	$ 352.2	$ 350.9	$ 343.8	$ 306.8	$ 312.7	$ 329.4	$ 328.0	$ 1,412.9	$ 1,276.9	$ 1,463.8
Segment operating income:
Total segment operating income									90.2	69.2	97.9
Asset impairment charge								$ (4.0)	0.0	(4.0)	0.0
Litigation settlement gains (judgment costs)				$ 3.3					3.3	0.0	(2.2)
Interest expense									(31.5)	(28.2)	(27.9)
Loss on extinguishment of debt									(11.0)	0.0	0.0
Income before income taxes									47.7	41.0	70.0
Capital expenditures:									27.9	28.5	36.5
Depreciation and amortization expense:									31.5	29.5	28.7
Identifiable assets:	1,132.5				974.3				1,132.5	974.3	942.1
Operating Segments
Segment operating income:
Total segment operating income									117.0	101.1	129.1
Segment Reconciling Items
Segment operating income:
Corporate costs									(30.1)	(27.9)	(29.0)
Corporate
Segment operating income:
Capital expenditures:									0.3	0.0	0.0
Depreciation and amortization expense:									0.5	0.6	1.2
Identifiable assets:	83.1				74.5				83.1	74.5	77.9
Supply Technologies
Segment operating income:
Capital expenditures:									3.3	6.1	3.7
Depreciation and amortization expense:									4.7	4.7	4.7
Identifiable assets:	344.4				262.0				344.4	262.0	276.3
Supply Technologies | Operating Segments
Net sales:
Net sales									561.8	502.1	578.7
Segment operating income:
Total segment operating income									45.9	40.0	50.3
Assembly Components
Segment operating income:
Capital expenditures:									18.6	16.9	27.3
Depreciation and amortization expense:									20.7	20.1	18.6
Identifiable assets:	351.4				332.9				351.4	332.9	344.8
Assembly Components | Operating Segments
Net sales:
Net sales									524.5	529.4	569.2
Segment operating income:
Total segment operating income									50.4	50.5	57.9
Engineered Products
Segment operating income:
Capital expenditures:									5.7	5.5	5.5
Depreciation and amortization expense:									5.6	4.1	4.2
Identifiable assets:	$ 353.6				$ 304.9				353.6	304.9	243.1
Engineered Products | Operating Segments
Net sales:
Net sales									326.6	245.4	315.9
Segment operating income:
Total segment operating income									$ 20.7	$ 10.6	$ 20.9