Net Fair Value of Commodity Price Risk (Detail) - USD ($) $ in Thousands	Jul. 16, 2016	Jan. 02, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Assets	$ 273
Liabilities	(13,248)	$ (14,887)
Net Fair Value	(12,975)	(14,887)
Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Assets	273
Liabilities	(12,232)	(11,946)
Net Fair Value	(11,959)	(11,946)
Level 2
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(1,016)	(2,941)
Net Fair Value	(1,016)	(2,941)
Other LongTerm Assets
Derivative Instruments, Gain (Loss) [Line Items]
Assets	273
Other LongTerm Assets | Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Assets	273
Other Current Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(13,248)	(14,867)
Other Current Liabilities | Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	(12,232)	(11,926)
Other Current Liabilities | Level 2
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities	$ (1,016)	(2,941)
Other LongTerm Liabilities
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities		(20)
Other LongTerm Liabilities | Level 1
Derivative Instruments, Gain (Loss) [Line Items]
Liabilities		$ (20)