Other Financial Information - Deferred Revenue (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Reported as:
Current	$ 750.2	$ 812.9
Long-term	383.8	410.5
Deferred revenue	1,134.0	1,223.4
Undelivered product commitments and other product deferrals
Deferred product revenue:
Deferred gross product revenue	109.8	141.7
Product
Deferred product revenue:
Deferred gross product revenue	109.8	141.7
Deferred cost of product revenue	(10.5)	(9.1)
Reported as:
Deferred revenue	99.3	132.6
Service
Reported as:
Deferred revenue	$ 1,034.7	$ 1,090.8