Segment Information Sales Including Intersegment Sales (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ 2,291.5	$ 2,383.0	$ 4,465.6	$ 4,678.8
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	2,302.4	2,394.3	4,484.0	4,700.6
Operating Segments | Passive Safety
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	1,925.3	2,013.8	3,755.7	3,965.3
Operating Segments | Electronics
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	377.1	380.5	728.3	735.3
Corporate and other
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	2.9	5.2	7.1	9.2
Intersegment Eliminations
Segment Reporting, Revenue Reconciling Item [Line Items]
Net sales	$ (13.8)	$ (16.5)	$ (25.5)	$ (31.0)