Net Fair Value of Commodity Price Risk (Detail) - USD ($) $ in Thousands	Apr. 20, 2019	Dec. 29, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	$ (22,668)	$ (8,935)
Net Fair Value	22,668	8,434
Assets		501
Net Fair Value	(22,668)	(8,434)
Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(22,668)	(8,935)
Net Fair Value	22,668	8,434
Assets		501
Net Fair Value	(22,668)	(8,434)
Other Current Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(20,570)	(7,732)
Other Current Liabilities | Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(20,570)	(7,732)
Other LongTerm Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(2,098)	(1,203)
Other LongTerm Liabilities | Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	$ (2,098)	(1,203)
Other Current Assets
Derivative Instruments, Gain (Loss) [Line Items]
Assets		501
Other Current Assets | Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Assets		$ 501