Preferred Stock - Summary of Allocation of Proceeds to and Changes in Carrying Value of Class B (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 28, 2012
Temporary Equity [Line Items]
Beginning Balance
Accretion	2,616
Ending Balance
Class B Preferred Stock [Member]
Temporary Equity [Line Items]
Issuance of Class B redeemable convertible preferred stock, net of allocation of proceeds	34,170
Issuance of Class B redeemable convertible preferred stock, net of allocation of proceeds	75,618
Reclassification upon conversion of Class B to common stock	$ (78,234)

Issuance of redeemable convertible preferred stock shares.

No definition available.

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- Definition

The cash inflow from issuance of callable preferred stock which is identified as being convertible to another type of financial security at the option of the issuer or the holder.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

+ Details

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- Definition

The difference between the carrying amount of a financial instrument subject to a registration payment arrangement recorded as temporary equity prior to adoption of FSP EITF 00-19-2 and the carrying amount reclassified to permanent equity upon the adoption of FSP EITF 00-19-2. Recorded as a cumulative effect adjustment to the beginning balance of retained earnings. Does not apply to registration payment arrangements that are no longer outstanding upon adoption of FSP EITF 00-19-2.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 40

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6445032&loc=d3e90193-114008

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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- Definition

Value of accretion of temporary equity to its redemption value during the period.

+ References

No definition available.

+ Details

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- Definition

Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

+ References

No definition available.

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