Changes in Accrued Warranties and Related Costs (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 28, 2015	Mar. 29, 2014	Mar. 28, 2015	Mar. 29, 2014
Movement in Standard Product Warranty Accrual [Roll Forward]
Beginning accrued warranty and related costs	$ 5,195us-gaap_StandardProductWarrantyAccrual	$ 3,980us-gaap_StandardProductWarrantyAccrual	$ 4,159us-gaap_StandardProductWarrantyAccrual	$ 2,967us-gaap_StandardProductWarrantyAccrual
Cost of warranty claims	(1,030)	(865)	(2,074)	(1,929)
Accruals for product warranty	978	1,253	3,058	3,330
Ending accrued warranty and related costs	$ 5,143us-gaap_StandardProductWarrantyAccrual	$ 4,368us-gaap_StandardProductWarrantyAccrual	$ 5,143us-gaap_StandardProductWarrantyAccrual	$ 4,368us-gaap_StandardProductWarrantyAccrual

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Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (c)(1),(c)(5)

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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Period Type:	instant

- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(2))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase in the liability for accruals related to extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(3))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

+ Details

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