Acquisitions - Allocation of Purchase Price (Details) (USD $) In Thousands, unless otherwise specified				12 Months Ended			12 Months Ended		3 Months Ended	12 Months Ended		12 Months Ended		12 Months Ended		3 Months Ended		0 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Isilon	Dec. 31, 2010 Isilon	Dec. 31, 2012 VMware Nicira	Dec. 31, 2012 Purchased / Developed technology Isilon	Dec. 31, 2010 Purchased / Developed technology Isilon	Dec. 31, 2012 Purchased / Developed technology VMware Nicira	Dec. 31, 2012 Customer Maintenance Relationships Isilon	Dec. 31, 2010 Customer Maintenance Relationships Isilon	Dec. 31, 2012 Customer Product Relationships Isilon	Dec. 31, 2010 Customer Product Relationships Isilon	Dec. 31, 2012 Tradename and trademark Isilon	Dec. 31, 2010 Tradename and trademark Isilon	Dec. 31, 2012 Tradename and trademark VMware Nicira	Dec. 31, 2010 In-process research and development Isilon	Aug. 24, 2012 In-process research and development VMware Nicira	Dec. 31, 2012 In-process research and development VMware Nicira
Business Acquisition [Line Items]
Finite-Lived Intangible Asset, Useful Life																		8 years
Purchase Price Allocation
Trade accounts receivable (approximates contractual value)					$ 38,565
Other current assets					17,448
Property and equipment					8,678
Intangible assets:
Intangible assets					469,400	334,600		115,300	266,000		142,900		159,600		7,700	20,100	43,900		48,500
Current liabilities					(51,910)
Deferred revenue					(37,800)
Goodwill	13,839,700	12,154,970	11,772,650		1,974,536	905,140
Deferred tax liabilities, net					(90,758)	(78,247)
Income tax payable					272	61,006
Other current liabilities, net of current assets						(863)
Total purchase price					$ 2,327,887	$ 1,099,624
Parenthetical
Weighted-average useful life				4 years 7 months 6 days			3 years 1 month 6 days		7 years	6 years 7 months 6 days		4 years 3 months 18 days		2 years 4 months 24 days		10 years