Allocation of Purchase Price (Detail) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Intangible assets:
Developed technology	$ 97,500,000	$ 158,860,000	$ 141,000,000
IPR&D			174,600,000
Customer relationships	58,400,000	74,280,000	291,800,000
Tradename and trademark	1,200,000	12,620,000	13,770,000
Non-competition agreements			1,200,000
Other		3,379,000
Total intangible assets	157,100,000	249,139,000	622,370,000
Goodwill	375,800,000	2,605,900,000	2,189,200,000
Isilon
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Trade accounts receivable (approximates contractual value)		38,565,000
Other current assets		17,448,000
Property and equipment		8,678,000
Intangible assets:
Developed technology		115,300,000
Customer maintenance relationships		142,900,000
Customer product relationships		159,600,000
Tradename		7,700,000
IPR&D		43,900,000
Total intangible assets		469,400,000
Goodwill		1,974,536,000
Current liabilities		(51,910,000)
Income tax payable		(272,000)
Deferred revenue		(37,800,000)
Deferred income taxes		(90,758,000)
Total purchase price		2,327,887,000
Data Domain
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Trade accounts receivable (approximates contractual value)			72,455,000
Other current assets			9,275,000
Property and equipment			40,403,000
Intangible assets:
Developed technology			106,300,000
Customer maintenance relationships			133,700,000
Customer product relationships			111,500,000
Tradename			6,400,000
IPR&D			174,600,000
Total intangible assets			532,500,000
Other long-term assets			60,000
Goodwill			1,658,321,000
Current liabilities			(67,212,000)
Income tax payable			(4,671,000)
Deferred revenue			(60,800,000)
Deferred income taxes			(152,818,000)
Long-term liabilities			(10,243,000)
Total purchase price			$ 2,017,270,000