Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 29, 2017	Sep. 29, 2017
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Derivative contracts designated as hedging instruments, Assets	$ 13,273	$ 13,932
Derivative contracts not designated as hedging instruments, Assets	893	284
Embedded derivatives, Assets	681	746
Derivative contracts designated as hedging instruments, Liabilities	364	464
Derivative contracts not designated as hedging instruments, Liabilities	1,445	2,440
Embedded derivatives, Liabilities	1,792	2,239
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated value of assets held for sale	16,844	19,835
Estimated value of liabilities held for sale	$ 5,189	$ 8,908