Financial Instruments - Changes in Financial Liabilities with Inputs Classified within Level 3 of Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 28, 2012	Dec. 30, 2011
Contingent consideration [Member]
Fair Value Assets Measured On Recurring Basis [Line Items]
Changes in financial liabilities with inputs classified within Level 3 of the fair value, beginning balance	$ 6,580	$ 25,502
Net Realized/ Unrealized Losses (Gains) Included in Earnings	(172)	169
Purchases and Issuances
Sales and Settlements	(6,003)	(15,000)
Transfers in and/or (out) of Level 3
Changes in financial liabilities with inputs classified within Level 3 of the fair value, ending balance	405	10,671
Common stock warrant liability [Member]
Fair Value Assets Measured On Recurring Basis [Line Items]
Changes in financial liabilities with inputs classified within Level 3 of the fair value, beginning balance	7,561	10,736
Net Realized/ Unrealized Losses (Gains) Included in Earnings	2,026	(1,458)
Purchases and Issuances
Sales and Settlements
Transfers in and/or (out) of Level 3
Changes in financial liabilities with inputs classified within Level 3 of the fair value, ending balance	9,587	9,278
Class B conversion liability [Member]
Fair Value Assets Measured On Recurring Basis [Line Items]
Changes in financial liabilities with inputs classified within Level 3 of the fair value, beginning balance		81,378
Net Realized/ Unrealized Losses (Gains) Included in Earnings		(13,620)
Purchases and Issuances
Sales and Settlements
Transfers in and/or (out) of Level 3
Changes in financial liabilities with inputs classified within Level 3 of the fair value, ending balance		$ 67,758

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Fair value measurement with unobservable inputs reconciliation recurring basis liability purchases and issuances.

+ References

No definition available.

+ Details

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability sales and settlement.

+ References

No definition available.

+ Details

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- Definition

Amount of net transfers into and out of financial instruments classified in shareholders' equity measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

+ Details

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- Definition

Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

-Subparagraph c(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.

+ Details

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- Definition

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

+ Details

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