Related Party Transactions - Additional Information (Detail) (USD $)	3 Months Ended
Dec. 27, 2013	Dec. 28, 2012	Sep. 27, 2013
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	$ (1,391,000)	$ 179,000
Carrying value of the equity investment in dpiX Holding	47,200,000		49,700,000
Purchases of glass transistor arrays from dpiX	$ 3,500,000	$ 10,800,000
Percentage of manufacturing capacity	50.00%
Percentage of fixed costs	50.00%

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.12)

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=16385135&loc=d3e33749-111570

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 9

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 45

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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- Definition

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

+ References

No definition available.

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- Definition

The percentage of fixed costs as defined in the agreement and determined at the beginning of each calendar year that the entity is required to pay.

+ References

No definition available.

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- Definition

The percentage of manufacturing capacity that the entity has the guaranteed right to purchase up to.

+ References

No definition available.

+ Details

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- Definition

The percentage of dpiX LLC's ownership interest in dpiX LLC.

+ References

No definition available.

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