Fair Value - Schedule of Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jul. 04, 2020	Dec. 28, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	$ (1,795)	$ (317)
Aluminum Forward Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	(1,803)	(317)
MTP Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	8
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	(1,795)	(317)
Significant Other Observable Inputs (Level 2) [Member] | Aluminum Forward Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	(1,803)	$ (317)
Significant Other Observable Inputs (Level 2) [Member] | MTP Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	$ 8