Changes In Fair Value of Level 3 Financial Assets (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
LenovoEMC
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of the period	$ 34		$ 33
Realized gain (loss) included in other income (expense)	0		1
Balance, end of the period	34		34
Auction Rate Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of the period	68	74	70	75
Calls at par value	0	0	1	0
Other than Temporary Impairment Losses, Investments	0	0	1	2
(Increase) decrease in previously recognized unrealized losses included in other comprehensive income	(1)	1	(1)	2
Balance, end of the period	$ 67	$ 75	$ 67	$ 75