Revenue from Contracts with Customers - EEGH - Remaining Performance Obligation (Details) $ in Millions	Sep. 30, 2021 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 24,138
EEGH
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	17,987
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-07-01 | EEGH
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 1,574
Performance obligations expected to be satisfied, expected timing of satisfaction, period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 2,761
Performance obligations expected to be satisfied, expected timing of satisfaction, period	12 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-07-01 | EEGH
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 16,413
Performance obligations expected to be satisfied, expected timing of satisfaction, period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-10-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligations expected to be satisfied	$ 21,377
Performance obligations expected to be satisfied, expected timing of satisfaction, period