RELATED PARTY TRANSACTIONS - Additional Information (Detail) - dpiX Holding - Affiliated Entity $ in Millions	3 Months Ended	6 Months Ended
Apr. 01, 2016 USD ($) member	Apr. 03, 2015 USD ($)	Apr. 01, 2016 USD ($) member	Apr. 03, 2015 USD ($)	Oct. 02, 2015 USD ($)
Related Party Transaction [Line Items]
Ownership interest in dpiX Holding LLC (as a percent)	40.00%		40.00%
Number of members \| member	2		2
dpiX Holding LLC's ownership interest in dpiX LLC (as a percent)	100.00%		100.00%
Income (Loss) on equity investment in affiliate	$ 0.6	$ 0.9	$ (0.1)	$ 0.5
Carrying value of the equity investment in dpiX Holding	47.7		47.7		$ 47.3
Purchases of glass transistor arrays from dpiX	5.4	$ 5.6	$ 10.4	$ 9.9
Percentage of manufacturing capacity			50.00%
Percentage of fixed costs			50.00%
Fixed cost commitments	$ 13.5		$ 13.5

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)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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+ References

Reference 1: 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=35755396&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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+ 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=56944662&loc=d3e3602-108585

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=35755396&loc=d3e33749-111570

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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-Section S99
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-Subparagraph (SX 210.5-03.12)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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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 calendar year.

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

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

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Related Party Transaction, Number Of Consortium Members

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