Other Financial Information, Deferred Revenue (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Deferred product revenue [Abstract]
Deferred revenue	$ 1,028.0	$ 923.4
Deferred Revenue Reported as [Abstract]
Deferred revenue, current	750.4	693.5
Deferred revenue, long-term	277.6	229.9
Sales Revenue, Product, Net [Member]
Deferred product revenue [Abstract]
Undelivered product commitments and other product deferrals	237.0	256.9
Distributor inventory and other sell-through items	100.0	138.4
Deferred gross product revenue	337.0	395.3
Deferred cost of product revenue	(59.5)	(99.4)
Deferred revenue	277.5	295.9
Sales Revenue, Service, Net [Member]
Deferred product revenue [Abstract]
Deferred revenue	$ 750.5	$ 627.5