Fair Value of Plan Assets of Defined Benefit Pension and Post-Retirement Plans (Detail) - USD ($) $ in Thousands	11 Months Ended	12 Months Ended
	Oct. 02, 2015	Sep. 29, 2017	Sep. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Beginning balance		$ 425,781
Company contribution	$ 9,500	10,100	$ 10,700
Ending balance		457,575	425,781
Pension Plan | Benefit Obligation
Defined Benefit Plan Disclosure [Line Items]
Other adjustments		(1,254)	(859)
Pension Plan | Plan Assets - Fair Value
Defined Benefit Plan Disclosure [Line Items]
Beginning balance		425,781	389,461
Currency translation adjustment		8,170	341
Realized and unrealized gain (loss) on plan assets		41,566	45,817
Plan participants contributions		318	376
Company contribution		6,681	12,041
Other adjustments		0	1,466
Expenses paid		(1,254)	(859)
Benefits paid		(23,687)	(22,862)
Ending balance	389,461	457,575	425,781
Pension Plan | Funded Status
Defined Benefit Plan Disclosure [Line Items]
Beginning balance		425,781
Ending balance		457,575	425,781
Other Postretirement Benefit Plan | Benefit Obligation
Defined Benefit Plan Disclosure [Line Items]
Other adjustments		0	0
Other Postretirement Benefit Plan | Plan Assets - Fair Value
Defined Benefit Plan Disclosure [Line Items]
Beginning balance		0	0
Currency translation adjustment		0	0
Realized and unrealized gain (loss) on plan assets		0	0
Plan participants contributions		0	0
Company contribution		550	530
Other adjustments		0	0
Expenses paid		0	0
Benefits paid		(550)	(530)
Ending balance	$ 0	0	0
Other Postretirement Benefit Plan | Funded Status
Defined Benefit Plan Disclosure [Line Items]
Beginning balance		$ 0
Ending balance			$ 0