Related Party Transactions - Additional Information (Detail) (USD $)	12 Months Ended
Sep. 27, 2013	Sep. 28, 2012	Sep. 30, 2011
Related Party Transaction [Line Items]
Ownership interest in dpiX Holding LLC	40.00%
dpiX Holding LLC's ownership interest in dpiX LLC	100.00%
Income (Loss) on equity investment in affiliate	$ 2,461,000	$ 245,000	$ 4,276,000
Carrying value of the equity investment in dpiX Holding	49,700,000	45,500,000
Loan agreement, amendment date	December 2011
Loan agreement, related party			8,800,000
Related party loan agreement, interest rate	prime plus 1%
Purchases of glass transistor arrays from dpiX	$ 25,900,000	$ 14,500,000	$ 23,300,000
Principal with accrued interest
Related Party Transaction [Line Items]
Number of installment payment	2

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amendment date

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Loan agreement related party amount repaid.

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Number of installments.

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Percentage of subsidiary ownership.

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- Definition

The stated interest rate per the agreement.

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