Derivative Financial Instruments - Summary of Pre-Tax Changes in Fair Value (Detail) - Commodity Contract [Member] - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss)	$ 297	$ (1,187)	$ (2,670)	$ (860)
Cost of Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss)	249	(674)	(2,516)	24
Selling, Delivery and Administrative Expenses [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Total gain (loss)	$ 48	$ (513)	$ (154)	$ (884)