Goodwill and Purchased Intangible Assets, Finite Lived Intangible Assets by Class (Details) (USD $)	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 591,000,000		$ 557,500,000
Finite-lived intangible assets, accumulated amortization	(470,700,000)		(443,600,000)
Finite-lived intangible assets, net	120,300,000		113,900,000
Indefinite-lived Intangible Assets	2,800,000		7,900,000
Indefinite-Lived Intangible Assets (Excluding Goodwill)	2,800,000		7,900,000
Intangible Assets Gross Excluding Goodwill	593,800,000		565,400,000
Purchased Intangible Assets, Accumulated Amortization	(470,700,000)		(443,600,000)
Purchased intangible assets, net	123,114,000		121,803,000
Total Finite and Indefinite-lived Intangible Assets, Acquired During the Period	28,400,000		116,500,000
Amortization of purchased intangible assets	27,100,000	[1]	8,600,000	[1]	15,400,000	[1]
Impairment of finite-lived intangible assets	0		0		0
In Process Research And Development [Member]
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, accumulated amortization
Technologies and Patents [Member]
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, gross	499,500,000		471,100,000
Finite-lived intangible assets, accumulated amortization	(404,200,000)		(381,400,000)
Finite-lived intangible assets, net	95,300,000		89,700,000
Other Intangible Assets [Member]
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, gross	91,500,000		86,400,000
Finite-lived intangible assets, accumulated amortization	(66,500,000)		(62,200,000)
Finite-lived intangible assets, net	$ 25,000,000		$ 24,200,000

[1] Amount includes amortization expense of purchased intangible assets in operating expenses and in cost of revenues.