Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 29, 2018	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	$ 1,014	$ 13,932
Derivative contracts not designated as hedging instruments, Assets	84	284
Embedded derivatives, Assets	3,298	746
Derivative contracts designated as hedging instruments, Liabilities	8,507	464
Derivative contracts not designated as hedging instruments, Liabilities	1,440	2,440
Embedded derivatives, Liabilities	494	2,239
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated value of assets held for sale	16,684	19,835
Estimated value of liabilities held for sale	$ 6,122	$ 8,908