Related Party Transactions - Additional Information (Detail) $ in Thousands	1 Months Ended	12 Months Ended
Oct. 31, 2013	Oct. 02, 2015 USD ($) member	Sep. 26, 2014 USD ($)	Sep. 27, 2013 USD ($)
Related Party Transaction [Line Items]
Income (Loss) on equity investment in affiliate		$ 335	$ (822)	$ 2,461
Carrying value of the equity investment		$ 49,700	49,700
dpiX \| Affiliated Entity
Related Party Transaction [Line Items]
Ownership interest in dpiX Holding LLC		40.00%
Number of members \| member		2
dpiX Holding LLC's ownership interest in dpiX LLC (as a percent)		100.00%
Income (Loss) on equity investment in affiliate		$ 100	(800)	2,500
Carrying value of the equity investment		47,300	49,700
Purchases of glass transistor arrays from dpiX		21,300	$ 20,900	$ 25,900
Percentage of manufacturing capacity	50.00%
Percentage of fixed costs	50.00%
Fixed cost commitments		$ 4,400

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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-Name Accounting Standards Codification

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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

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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

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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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The amount of fixed manufacturing costs required to be paid during the fiscal year.

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No definition available.

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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.

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No definition available.

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

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Related Party Transaction, Number Of Consortium Members

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