Segment Information (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) segments	Sep. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segments			2
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenues	$ 243.1	$ 246.7	$ 618.7	$ 626.1
Reconciliation of Net Earnings from Segments [Abstract]
Interest expense, net	5.6	3.6	15.1	9.1
Earnings before income taxes and discontinued operations	20.9	4.7	5.4	27.8
(Benefit from) provision for income taxes	0.0	(0.1)	3.8	4.7
Earnings from continuing operations	20.9	4.8	1.6	23.1
Operating Segments
Reconciliation of Net Earnings from Segments [Abstract]
(Loss) earnings before interest and income taxes	41.8	24.7	60.9	77.6
Operating Segments \| Mobile Consumer Electronics
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenues	140.4	141.3	305.9	308.2
Reconciliation of Net Earnings from Segments [Abstract]
(Loss) earnings before interest and income taxes	22.0	7.0	7.5	30.9
Operating Segments \| Specialty Components
Reconciliation from Segment Totals to Consolidated [Abstract]
Revenues	102.7	105.4	312.8	317.9
Reconciliation of Net Earnings from Segments [Abstract]
(Loss) earnings before interest and income taxes	19.8	17.7	53.4	46.7
Corporate
Reconciliation of Net Earnings from Segments [Abstract]
Corporate expense / other	15.3	16.4	40.4	40.7
Segment Reconciling Items
Reconciliation of Net Earnings from Segments [Abstract]
Interest expense, net	$ (5.6)	$ (3.6)	$ (15.1)	$ (9.1)

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