Components of Other Current Assets (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 27, 2015	Sep. 26, 2014
Other Assets, Current [Line Items]
Purchase Price Note Receivable from Beneq, current portion	$ 1,300plnr_PromissoryNoteCurrent	$ 650plnr_PromissoryNoteCurrent
Component Device Receivable from Beneq, current portion	492us-gaap_NontradeReceivablesCurrent	382us-gaap_NontradeReceivablesCurrent
Other	3,243us-gaap_OtherAssetsMiscellaneousCurrent	2,877us-gaap_OtherAssetsMiscellaneousCurrent
Total other current assets	$ 5,035us-gaap_OtherAssetsCurrent	$ 3,909us-gaap_OtherAssetsCurrent

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Promissory Note Current

+ References

No definition available.

+ Details

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- Definition

The sum of amounts currently receivable other than from customers. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within 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 210.5-02.8)

-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 8

-Article 5

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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