Fair Value of Financial Instruments - Deferred Compensation Plan, Commodity Hedging Agreements and Acquisition Related Contingent Consideration (Detail) - USD ($) $ in Thousands	Sep. 27, 2015	Jun. 28, 2015	Dec. 29, 2014	Dec. 28, 2014	Sep. 28, 2014	Jun. 29, 2014	Dec. 30, 2013
Assets
Commodity hedging agreements	$ 800
Liabilities
Contingent consideration liability	93,064	$ 94,068	$ 46,850		$ 13,000	$ 13,000	$ 0
Level 1 [Member]
Assets
Deferred compensation plan assets	19,660			$ 18,580	18,015
Liabilities
Deferred compensation plan liabilities	19,660			18,580	18,015
Level 2 [Member] | Commodity Hedging Agreements [Member]
Assets
Commodity hedging agreements	39			0	552
Liabilities
Commodity hedging agreements	2,275			0	0
Level 3 [Member]
Liabilities
Contingent consideration liability	$ 93,064			$ 46,850	$ 13,000