Segment Information Depreciation and Amortization (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Reconciliation of Depreciation and Amortization by Segment [Line Items]
Depreciation and amortization	$ 109.8	$ 114.8
Passive Safety
Reconciliation of Depreciation and Amortization by Segment [Line Items]
Depreciation and amortization	82.6	73.1
Electronics
Reconciliation of Depreciation and Amortization by Segment [Line Items]
Depreciation and amortization	26.3	38.8
Corporate and other
Reconciliation of Depreciation and Amortization by Segment [Line Items]
Depreciation and amortization	$ 0.9	$ 2.9