Dispositions and Impairments (Financial Results That Have Been Reclassified from Continuing Operations and Included in Discontinued Operations) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Other (Income) and Deductions
Net Income from Discontinued Operations, Net of Taxes	$ 5	$ (33)	$ 65	$ 80	$ 69	$ 107	$ 76	$ 74	$ 117	$ 326	$ 230
Less: Net Income Attributable to Noncontrolling Interests									6	12	16
Net Income from Discontinued Operations									111	314	214
Transaction costs									59	8
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									405	754	501
Operating Expenses
Cost of gas and other — non-utility									15	21	18
Operation and maintenance									123	138	103
Depreciation and amortization									82	151	94
Taxes other than income									13	15	8
Asset (gains) losses and impairments, net									17	(2)	1
Operating Expenses									250	323	224
Operating Income									155	431	277
Other (Income) and Deductions
Interest expense									50	113	73
Interest income									(4)	(9)	(8)
Other income									(62)	(129)	(100)
Other expenses									0	0	1
Other (Income) and Deductions									(16)	(25)	(34)
Income from Discontinued Operations Before Income Taxes									171	456	311
Income Tax Expense									54	130	81
Net Income from Discontinued Operations, Net of Taxes									117	326	230
Less: Net Income Attributable to Noncontrolling Interests									6	12	16
Net Income from Discontinued Operations									$ 111	$ 314	$ 214