Components of Other Assets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 27, 2015	Sep. 26, 2014
Other Assets Noncurrent [Line Items]
Purchase Price Note Receivable from Beneq, non-current portion	$ 1,300plnr_PromissoryNoteNoncurrent	$ 1,950plnr_PromissoryNoteNoncurrent
Component Device Receivable from Beneq, non-current portion	1,857us-gaap_NontradeReceivablesNoncurrent	2,741us-gaap_NontradeReceivablesNoncurrent
Other	1,708	2,559
Total other assets	$ 4,865us-gaap_OtherAssetsNoncurrent	$ 7,250us-gaap_OtherAssetsNoncurrent

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Promissory Note Noncurrent

+ References

No definition available.

+ Details

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- Definition

The noncurrent portion of the receivable other than from customers, that is amounts expected to be collected after one year or the normal operating cycle, if longer.

+ 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 210.5-02.17)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 17

-Article 5

+ Details

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- Definition

Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

+ References

No definition available.

+ Details

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- Definition

Aggregate carrying amount, as of the balance sheet date, of noncurrent assets not separately disclosed in the balance sheet. Noncurrent assets are expected to be realized or consumed after one year (or the normal operating cycle, if longer).

+ References

+ Details

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