Goodwill and Purchased Intangible Assets, Purchased Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, net	$ 69.1
Total purchased intangible assets, gross	690.2	$ 646.9
Total purchased intangible assets, accumulated amortization	(568.4)	(560.3)
Total purchased intangible assets, impairments and other charges	(52.7)	(52.7)
Total purchased intangible assets, net	69.1	33.9
Technologies and patents [Member]
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, gross	604.8	567.7
Finite-lived intangible assets, accumulated amortization	(498.1)	(491.8)
Finite-lived intangible assets, impairments and other charges	(49.9)	(49.9)
Finite-lived intangible assets, net	56.8	26.0
Customer contracts, support agreements, and related relationships [Member]
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, gross	83.4	78.1
Finite-lived intangible assets, accumulated amortization	(69.2)	(67.8)
Finite-lived intangible assets, impairments and other charges	(2.8)	(2.8)
Finite-lived intangible assets, net	11.4	7.5
Other intangible assets [Member]
Purchased Intangible Assets [Line Items]
Finite-lived intangible assets, gross	2.0	1.1
Finite-lived intangible assets, accumulated amortization	(1.1)	(0.7)
Finite-lived intangible assets, impairments and other charges	0.0	0.0
Finite-lived intangible assets, net	$ 0.9	$ 0.4