Intrinsic Value and Weighted-average Remaining Life Related to Outstanding and Unvested Stock Options (Detail) (Employee Stock Option, USD $) In Thousands, unless otherwise specified	Oct. 02, 2011 Year	Oct. 03, 2010 Year	Sep. 27, 2009 Year
Employee Stock Option
Intrinsic Value
Outstanding	$ 12,684	$ 13,156	$ 11,356
Unvested	$ 2,414		$ 180
Weighted- Average Remaining Life
Outstanding	3.1	3.4	4.3
Unvested	7.8	3.4	3.9

Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract]

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Expected to Vest, Aggregate Intrinsic Value

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Share Based Compensation Arrangement By Share Based Payment Award Options Expected To Vest Weighted Average Remaining Contractual Term 1

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Term [Abstract]

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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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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The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

-SubTopic 10

-Topic 718

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

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