Preproduction Costs Related to Long-Term Supply Arrangements - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 25, 2017	Jun. 30, 2018	Jun. 25, 2017
Deferred Revenue [Abstract]
Deferred revenue, revenue recognized	$ 2.1	$ 1.8	$ 3.7	$ 3.5

Amount of revenue recognized that was previously reported as deferred or unearned revenue.

No definition available.

Name:	us-gaap_DeferredRevenueRevenueRecognized1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration