Revenue Recognition Remaining Performance Obligations (Details) $ in Millions	Mar. 31, 2021 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized	$ 813
Corporate and Other [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized	$ 813
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of satisfaction, period	1 year
Revenue expected to be recognized	$ 259
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-04-01 | Corporate and Other [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized	$ 259
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Expected timing of satisfaction, period
Revenue expected to be recognized	$ 554
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-04-01 | Corporate and Other [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue expected to be recognized	$ 554