Stockholders' Equity And Stock-Based Compensation (Forfeiture Rates) (Details)	12 Months Ended
Sep. 25, 2015	Sep. 26, 2014	Sep. 27, 2013
Stockholders' Equity And Stock-Based Compensation [Abstract]
Estimated forfeiture rate, percent	9.98%	6.13%	6.13%

Share-based Compensation Arrangement by Share-based Payment Award, Estimated Forfeiture Rate

No definition available.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration