Leases Lessor (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019		Dec. 31, 2018	Dec. 31, 2017
Lessor, Lease, Description [Line Items]
Lease Income	$ 600,000,000
Variable Lease, Income	130,000,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	8,505,000,000		$ 8,227,000,000
Sales-type and Direct Financing Leases, Profit (Loss)	36,000,000	[1]	$ 0	$ 0
Sales-type and Direct Financing Leases, Lease Receivable, Fiscal Year Maturity [Abstract]
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Next Twelve Months	2,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Two Years	2,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Three Years	2,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Four Years	2,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Five Years	2,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received, Thereafter	38,000,000
Sales-type and Direct Financing Leases, Lease Receivable, Payments to be Received	48,000,000
Lessor, Operating Lease, Payments, Fiscal Year Maturity [Abstract]
Lessor, Operating Lease, Payments to be Received, Next Twelve Months	504,000,000
Lessor, Operating Lease, Payments to be Received, Two Years	474,000,000
Lessor, Operating Lease, Payments to be Received, Three Years	459,000,000
Lessor, Operating Lease, Payments to be Received, Four Years	395,000,000
Lessor, Operating Lease, Payments to be Received, Five Years	396,000,000
Lessor, Operating Lease, Payments to be Received, Thereafter	1,463,000,000
Lessor, Operating Lease, Payments to be Received	3,691,000,000
Sales-type and Direct Financing Leases, Lease Receivables, Gross Difference, Amount [Abstract]
Sales-type and Direct Financing Leases, Lease Receivable, Undiscounted Excess Amount	26,000,000
Sales-type and Direct Financing Leases, Lease Receivable	22,000,000
Distributed Energy [Member]
Lessor, Lease, Description [Line Items]
Sales-type and Direct Financing Leases, Profit (Loss)	(36,000,000)
Property Subject to Operating Lease [Member]
Lessor, Lease, Description [Line Items]
Property, Plant and Equipment, Gross	2,900,000,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 707,000,000

[1] Related to losses recognized at commencement of sales-type leases at Distributed Energy. See Note 14—Leases for further information.