Stockholders' Equity And Stock-Based Compensation (Schedule of Stock-Based Compensation By Classification) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 26, 2014	Sep. 27, 2013	Sep. 28, 2012
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 65,680	$ 64,328	$ 47,581
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	19,315	19,316	14,930
Allocated Share-based Compensation Expense, Net of Tax	46,365	45,012	32,651
Cost of products [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	812	765	675
Cost of services [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	402	387	239
Research and development [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	18,510	17,117	11,553
Sales and marketing [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	23,236	21,507	16,233
General and administrative [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	22,720	22,685	18,881
Restructuring Charges [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 0	$ 1,867	$ 0