Schedule of Goodwill (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2017 USD ($)
Goodwill [Line Items]
Carrying amount at beginning of year	$ 1,870.7
Acquisition	16.9
Effect of currency translation	7.8
Carrying amount at end of year	1,895.4
Passive Safety
Goodwill [Line Items]
Carrying amount at beginning of year	1,380.6
Effect of currency translation	4.8
Carrying amount at end of year	1,385.4
Electronics
Goodwill [Line Items]
Carrying amount at beginning of year	490.1
Acquisition	16.9
Effect of currency translation	3.0
Carrying amount at end of year	$ 510.0