Acquisitions (Purchase Price Allocation) (Details) - USD ($) $ in Thousands		12 Months Ended
	Oct. 31, 2014	Sep. 25, 2015	Sep. 26, 2014	Sep. 27, 2013
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 45,600
Goodwill		307,708	$ 277,574	$ 279,724
Doremi Labs [Member]
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets		17,231
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Inventory		16,372
Goodwill		39,672
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities		(11,653)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities		(8,820)
Payments to Acquire Businesses, Gross	$ 98,402
Total purchase price		98,402
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		45,600
Business Combination, Contingent Consideration, Liability	20,000	740
Gross purchase price	$ 99,142
Customer Relationships [Member] | Doremi Labs [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 25,600
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		10 years
Developed Technology Rights [Member] | Doremi Labs [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 17,500
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		7 years 6 months
Trade Names [Member] | Doremi Labs [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 1,300
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		1 year
Order or Production Backlog [Member] | Doremi Labs [Member]
Business Acquisition [Line Items]
Finite-lived Intangible Assets Acquired		$ 1,200
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life		1 year