Net Share-Based Compensation Expense (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 27, 2013	Dec. 28, 2012
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expenses	$ 9,000	$ 10,200
Taxes on earnings	(2,798)	(3,169)
Net share-based compensation expense	6,246	6,994
Cost of revenues - Product
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expenses	707	1,111
Cost of revenues - Service
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expenses	947	363
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expenses	1,301	1,739
Selling, general and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expenses	$ 6,089	$ 6,950