Schedule of Financial Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 28, 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	$ 1,374	$ 13,932
Derivative contracts not designated as hedging instruments, Assets	38	284
Embedded derivatives, Assets	1,296	746
Derivative contracts designated as hedging instruments, Liabilities	6,756	464
Derivative contracts not designated as hedging instruments, Liabilities	1,026	2,440
Embedded derivatives, Liabilities	684	2,239
Level 3
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Estimated value of assets held for sale	4,225	19,835
Estimated value of liabilities held for sale	$ 144	$ 8,908