Goodwill and Purchased Intangible Assets, Purchased Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012
Purchased Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 657.1				$ 647.2
Finite-Lived Intangible Assets, Accumulated Amortization	(510.6)				(503.0)
Finite-lived Intangible Assets, Impairments and Other Charges	(32.7)				(32.7)
Finite-Lived Intangible Assets, Net	113.8				111.5
Total purchased intangible assets, gross	674.5				664.6
Total purchased intangible assets, Accumulated Amortization	(510.6)				(503.0)
Total purchased intangible assets, impairments and other charges	(32.7)				(32.7)
Total purchased intangible assets, net	131.2				128.9
Amortization of purchased intangible assets	7.5	[1]	7.3	[1]
Impairment of Intangible Assets, Finite-lived	0		0
In process research and development [Member]
Purchased Intangible Assets [Line Items]
Indefinite-lived Intangible Assets	17.4				17.4
Indefinite-Lived Intangible Assets, Impairments and Other Charges	0				0
Technologies and patents [Member]
Purchased Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	564.0				554.1
Finite-Lived Intangible Assets, Accumulated Amortization	(431.7)				(425.0)
Finite-lived Intangible Assets, Impairments and Other Charges	(30.5)				(30.5)
Finite-Lived Intangible Assets, Net	101.8				98.6
Customer contracts, support agreements, and related relationships [Member]
Purchased Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	74.3				74.3
Finite-Lived Intangible Assets, Accumulated Amortization	(60.1)				(59.2)
Finite-lived Intangible Assets, Impairments and Other Charges	(2.2)				(2.2)
Finite-Lived Intangible Assets, Net	12.0				12.9
Other intangible assets [Member]
Purchased Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	18.8				18.8
Finite-Lived Intangible Assets, Accumulated Amortization	(18.8)				(18.8)
Finite-lived Intangible Assets, Impairments and Other Charges	0				0
Finite-Lived Intangible Assets, Net	$ 0				$ 0

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