Contractual Terms for Stock Option Grants (Detail)	12 Months Ended
Sep. 29, 2012
Awards Granted Prior to January 2005
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, contractual term	10 years
Awards Granted January 2005 through December 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, contractual term	7 years
Awards Granted After December 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, contractual term	10 years

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Period Type:	duration