Retirement Plan Benefits - Additional Information (Details) - USD ($)	12 Months Ended			96 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Employer matching contribution percentage	6.00%
Employer matching contribution, amount per quarter	$ 750
Allocated Share-based Compensation Expense	1,093,000,000	$ 1,021,000,000	$ 935,000,000
Defined Contribution Plan, Employer Discretionary Contribution Amount	107,000,000	105,000,000	91,000,000
Fair value of company stock fund held by Pension Plan	453,000,000	486,000,000	$ 449,000,000	$ 453,000,000
Under-funded status of Pension Plan	72,000,000	$ 68,000,000		72,000,000
Accumulated actuarial loss and prior services cost reclassified from accumulated comprehensive loss to a component of net periodic benefit cost	12,000,000
Pension Plans net losses, primarily the result of a decrease in the discount rate at the end of 2015	14,000,000			$ 14,000,000
Total balance included in accumulated other comprehensive loss that will be recognized as a component of net periodic benefit cost in 2016	$ 13,000,000
Concentration risk, percentage of Pension Plan net assets	5.00%	5.00%
EMC | Maximum
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation program limit for employee's investment allocation in the company stock fund				30.00%
Retirement Benefit Stock Match
Defined Benefit Plan Disclosure [Line Items]
Allocated Share-based Compensation Expense	$ 47,000,000
Defined Contribution Plan, Employer Discretionary Contribution Amount	$ 3,000