Other Financial Information (Revenue) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2018 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	11 months 29 days
Revenue Recognition Expected by Period	$ 895.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01 | Product
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	144.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-04-01 | Service
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	$ 751.9
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	2 years
Revenue Recognition Expected by Period	$ 343.3
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01 | Product
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	19.1
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01 | Service
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	$ 324.2
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01
Disaggregation of Revenue [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Revenue Recognition Expected by Period	$ 25.3
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01 | Product
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	3.3
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01 | Service
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	22.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	1,264.5
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | Product
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	166.4
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | Service
Disaggregation of Revenue [Line Items]
Revenue Recognition Expected by Period	$ 1,098.1