Business Segments and Geographic Information - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
Mar. 28, 2015 Segment Customer	Mar. 29, 2014 Customer	Mar. 28, 2015 Segment Customer	Mar. 29, 2014 Customer	Sep. 27, 2014 Customer
Segment Reporting Disclosure [Line Items]
Number of reportable segments	4us-gaap_NumberOfOperatingSegments		4us-gaap_NumberOfOperatingSegments
Revenues	$ 655,500,000us-gaap_Revenues	$ 625,000,000us-gaap_Revenues	$ 1,308,300,000us-gaap_Revenues	$ 1,237,400,000us-gaap_Revenues
Customers with balances greater than 10% of accounts receivable	0		0		0
Customer represented greater than 10% of consolidated revenues	0	0	0	0
Countries with greater than 10% of consolidated revenue	0		0
Number of reportable segments			4us-gaap_NumberOfReportableSegments
Intersegment
Segment Reporting Disclosure [Line Items]
Revenues	$ 0	$ 0	$ 0	$ 0

Number of countries with greater than 10% of consolidated revenue

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- Definition

Number of customers accounting for more than ten percent of accounts receivable.

+ References

No definition available.

+ Details

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- Definition

Number of customers accounting for more than ten percent of revenue.

+ References

No definition available.

+ Details

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- Details

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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- Details

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