Fair Value - Schedule of Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Oct. 03, 2020	Dec. 28, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	$ 300	$ (317)
Aluminum Forward Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	330	(317)
MTP Contracts [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	(30)
Significant Other Observable Inputs (Level 2) [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Assets (Liabilities)	300	(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)	330	$ (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)	$ (30)