Changes In Outstanding Options Granted Under Equity Incentive Plans (Detail) - $ / shares	11 Months Ended	12 Months Ended
	Oct. 02, 2015	Sep. 29, 2017	Sep. 30, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding, beginning of year, Shares Subject to Option	1,362,793	1,390,956	1,358,921
Granted, Shares Subject to Option	203,200	242,200	221,200
Exercised, Shares Subject to Options	(182,322)	(492,968)	(112,790)
Forfeited/cancelled Shares Subject to Option	(24,750)	(63,450)	(76,375)
Outstanding, end of year, Shares Subject to Option	1,358,921	1,076,738	1,390,956
Exercisable, end of year, Shares Subject to Option	824,496	594,963	918,706
Outstanding, beginning of year, Weighted Average Exercise Price	$ 60.16	$ 72.09	$ 68.18
Granted, Weighted Average Exercise Price	107.34	81.60	90.16
Exercised, Weighted Average Exercise Price	50.94	51.70	48.61
Forfeited/cancelled Weighted Average Exercise Price	74.73	93.63	89.56
Outstanding, end of year, Weighted Average Exercise Price	68.18	82.30	72.09
Exercisable, end of year, Weighted Average Exercise Price	$ 55.58	$ 76.66	$ 61.03