Segment Information - Additional Information (Detail) (USD $) In Millions, unless otherwise specified					3 Months Ended		9 Months Ended			12 Months Ended	9 Months Ended
	Sep. 30, 2014 United States	Dec. 31, 2013 United States	Sep. 30, 2014 International	Dec. 31, 2013 International	Sep. 30, 2014 Geographic Concentration Sales Revenue, Segment Country	Sep. 30, 2013 Geographic Concentration Sales Revenue, Segment Country	Sep. 30, 2014 Geographic Concentration Sales Revenue, Segment Country	Sep. 30, 2013 Geographic Concentration Sales Revenue, Segment Country	Sep. 30, 2014 Geographic Concentration Long-lived Assets, Total Country	Dec. 31, 2013 Geographic Concentration Long-lived Assets, Total Country	Sep. 30, 2014 EMC Information Infrastructure segment
Segment Reporting Information [Line Items]
Number of operating segments											3
Number of countries other than the US that accounted for 10% or more					0	0	0	0	0	0
Long-lived assets, excluding financial instruments, deferred tax assets, goodwill and intangible assets	$ 4,337	$ 4,433	$ 973	$ 877