Intangibles and Goodwill - Changes in Carrying Amount of Goodwill (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Roll Forward]
Balance, beginning of the year	$ 14,424us-gaap_Goodwill	$ 13,840us-gaap_Goodwill
Goodwill resulting from acquisitions	1,715us-gaap_GoodwillAcquiredDuringPeriod	597us-gaap_GoodwillAcquiredDuringPeriod
Finalization of purchase price allocations and other, net	(5)	(13)
Goodwill transferred in formation of Pivotal	0us-gaap_GoodwillOtherChanges	0us-gaap_GoodwillOtherChanges
Balance, end of the year	16,134us-gaap_Goodwill	14,424us-gaap_Goodwill
Information Storage
Goodwill [Roll Forward]
Balance, beginning of the year	7,486	7,442
Goodwill resulting from acquisitions	774	145
Finalization of purchase price allocations and other, net	0	11
Goodwill transferred in formation of Pivotal	6	112
Balance, end of the year	8,266	7,486
Enterprise Content Division
Goodwill [Roll Forward]
Balance, beginning of the year	1,487	1,484
Goodwill resulting from acquisitions	0	1
Finalization of purchase price allocations and other, net	(1)	2
Goodwill transferred in formation of Pivotal	0	0
Balance, end of the year	1,486	1,487
RSA Information Security
Goodwill [Roll Forward]
Balance, beginning of the year	2,203	2,022
Goodwill resulting from acquisitions	0	181
Finalization of purchase price allocations and other, net	0	0
Goodwill transferred in formation of Pivotal	0	0
Balance, end of the year	2,203	2,203
Pivotal
Goodwill [Roll Forward]
Balance, beginning of the year	177	0
Goodwill resulting from acquisitions	0	37
Finalization of purchase price allocations and other, net	0	0
Goodwill transferred in formation of Pivotal	(6)	(140)
Balance, end of the year	171	177
VMware Virtual Infrastructure Within EMC Corp
Goodwill [Roll Forward]
Balance, beginning of the year	3,071	2,892
Goodwill resulting from acquisitions	941	233
Finalization of purchase price allocations and other, net	(4)	(26)
Goodwill transferred in formation of Pivotal	0	28
Balance, end of the year	$ 4,008	$ 3,071

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

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-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

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