Business Combinations, Intangibles and Goodwill - Goodwill (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Goodwill [Roll Forward]
Balance, beginning of the period	$ 16,134us-gaap_Goodwill
Goodwill resulting from acquisitions	38us-gaap_GoodwillAcquiredDuringPeriod
Finalization of purchase price allocations and other, net	2
Balance, end of the period	16,174us-gaap_Goodwill
Information Storage
Goodwill [Roll Forward]
Balance, beginning of the period	8,266
Goodwill resulting from acquisitions	21
Finalization of purchase price allocations and other, net	2
Balance, end of the period	8,289
Information Intelligence Group
Goodwill [Roll Forward]
Balance, beginning of the period	1,486
Goodwill resulting from acquisitions	0
Finalization of purchase price allocations and other, net	0
Balance, end of the period	1,486
RSA Information Security
Goodwill [Roll Forward]
Balance, beginning of the period	2,203
Goodwill resulting from acquisitions	0
Finalization of purchase price allocations and other, net	0
Balance, end of the period	2,203
Pivotal
Goodwill [Roll Forward]
Balance, beginning of the period	171
Goodwill resulting from acquisitions	0
Finalization of purchase price allocations and other, net	0
Balance, end of the period	171
VMware Virtual Infrastructure within EMC
Goodwill [Roll Forward]
Balance, beginning of the period	4,008
Goodwill resulting from acquisitions	17
Finalization of purchase price allocations and other, net	0
Balance, end of the period	$ 4,025

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

+ Details

Name:	us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

+ Details

Name:	us-gaap_GoodwillPurchaseAccountingAdjustments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_GoodwillRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=emc_InformationIntelligenceGroupMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=emc_InformationStorageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=emc_PivotalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=emc_RsaInformationSecurityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=emc_VmwareVirtualInfrastructureWithinEmcCorpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: