Quarterly Financial Data - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2011	Dec. 31, 2010
Special tax charge related to our tax-related reorganizations		$ 83.3
Special tax charge related to our tax-related reorganizations, per diluted shares		$ 0.04
Charge related to expansion of customer remediation programs resulting from cyber attacks	56.2
Charge related to expansion of customer remediation programs resulting from cyber attacks, per diluted share	$ 0.03
Gain on sale of VMware's strategic investment	$ 28.9
Gain on sale of VMware's strategic investment, per diluted share	$ 0.01