Pre-Production Costs Related to Long-Term Supply Agreements (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Dec. 31, 2016
Pre Production Costs Related to Long Term Supply Arrangements [Line Items]
Pre-production E&D costs for which reimbursement is contractually guaranteed by the customer	$ 190.8	$ 110.5
Pre-production tooling costs related to customer-owned tools for which reimbursement is contractually guaranteed by the customer	93.5	61.5
Cash collected related to E&D and tooling costs	247.7	$ 168.9
Recoverable customer E&D and tooling	286.5		$ 229.3
Current
Pre Production Costs Related to Long Term Supply Arrangements [Line Items]
Recoverable customer E&D and tooling	232.5		185.9
Long-term
Pre Production Costs Related to Long Term Supply Arrangements [Line Items]
Recoverable customer E&D and tooling	$ 54.0		$ 43.4