Discontinued Operations (Financial Results That Have Been Reclassified from Continuing Operations and Included in Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Other (Income) and Deductions
Net Income from Discontinued Operations, Net of Taxes	$ 0	$ 80
Less: Net Income Attributable to Noncontrolling Interests	0	3
Net Income from Discontinued Operations	$ 0	77
Transaction costs		10
DT Midstream | Discontinued operations, spinoff
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Operating Revenues — Non-utility operations		197
Operating Expenses
Cost of gas and other — non-utility		5
Operation and maintenance		41
Depreciation and amortization		41
Taxes other than income		7
Asset (gains) losses and impairments, net		(1)
Operating Expenses		93
Operating Income		104
Other (Income) and Deductions
Interest expense		26
Interest income		(3)
Other income		(33)
Other (Income) and Deductions		(10)
Income from Discontinued Operations Before Income Taxes		114
Income Tax Expense		34
Net Income from Discontinued Operations, Net of Taxes		80
Less: Net Income Attributable to Noncontrolling Interests		3
Net Income from Discontinued Operations		$ 77