Revenue Recognition Remaining Performance Obligations (Details) $ in Millions	Sep. 30, 2020 USD ($)
Revenue Recognition and Deferred Revenue [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 596
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-10-01
Revenue Recognition and Deferred Revenue [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 53
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue Recognition and Deferred Revenue [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 198
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue Recognition and Deferred Revenue [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 139
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year