Summary of Significant Accounting Policies (Details 4)	12 Months Ended
Sep. 28, 2014
Pre-opening Expenses [Abstract]
Average period for pre-opening rent expense (in months)	9 months
Average period for pre-opening costs other than rent (in days)	60 days
Stock Purchase Plan [Abstract]
Minimum service hours for stock purchase plan eligibility	400 hours
Percentage discount from purchase date market value under stock purchase plan	5.00%
Stock Option [Member]
Stock Incentive Plan [Abstract]
Period from grant date to beginning of options vesting	1 year
Stock Option [Member] \| Option 1 [Member]
Stock Incentive Plan [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	5 years
Stock Option [Member] \| Option 2 [Member]
Stock Incentive Plan [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	9 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	7 years
Stock Option [Member] \| Option 3 [Member]
Stock Incentive Plan [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Restricted Stock [Member] \| Option 1 [Member]
Stock Incentive Plan [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Restricted Stock [Member] \| Option 2 [Member]
Stock Incentive Plan [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Restricted Stock [Member] \| Option 3 [Member]
Stock Incentive Plan [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	6 years

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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

-Subparagraph (a)(1)

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- Definition

Discount rate from fair value on offering date that participants pay for shares.

+ References

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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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

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

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- Definition

Average period of time prior to new store openings during which pre-opening costs other than rent are expensed as incurred, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Average period of time prior to new store openings during which rent expense is incurred and expensed as a pre-opening cost, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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Represents the period of time from grant date until the employee's right to exercise a share-based compensation award begins to vest, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

This element represents the minimum service hours required for employee eligibility in the entity's stock purchase plan, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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