Employee Stock Plans - Summary the Effect of Recording Pre-Tax Share-Based Compensation Expense for Equity Incentive Awards (Detail) - USD ($) $ in Thousands	12 Months Ended
	Oct. 02, 2015	Sep. 26, 2014	Sep. 27, 2013
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 46,303	$ 39,636	$ 42,637
Equity Option
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	11,301	9,489	10,577
Restricted Stock Units and Restricted Stock Awards
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	31,364	26,576	28,229
Employee Stock Purchase Plans
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total share-based compensation expense	$ 3,638	$ 3,571	$ 3,831