Dispositions (Narrative) (Details) - USD ($) $ in Millions			6 Months Ended					9 Months Ended	35 Months Ended
Dispositions (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Aug. 04, 2025	Jun. 30, 2028	Dec. 31, 2027	Jun. 30, 2027	Dec. 31, 2026	Jun. 30, 2026	Sep. 30, 2024	Jun. 30, 2028	Sep. 30, 2025	Dec. 31, 2024	Oct. 25, 2023
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Aggregate investment from noncontrolling owner								$ 47
Current liabilities associated with assets held for sale										$ 57	$ 132
Florida Progress LLC
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investment Agreement, termination fee		$ 240
Florida Progress LLC \| Forecast
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Noncontrolling ownership percentage			19.70%				9.20%		19.70%
Aggregate investment from noncontrolling owner			$ 1,000	$ 1,500	$ 500	$ 200	$ 2,800		$ 6,000
Discontinued Operations, Disposed of by Sale \| Piedmont Tennessee Disposal Group \| Forecast
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration to be received	$ 2,480
Purchase Agreement termination fee, percentage	6.50%
Discontinued Operations, Disposed of by Sale \| Commercial Renewables
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration to be received												$ 1,100
Consideration period												18 months
Discontinued Operations, Disposed of by Sale \| Commercial Renewables \| Noncurrent assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration to be received											551
Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current liabilities associated with assets held for sale										57	132
Discontinued Operations, Held-for-sale \| Piedmont Tennessee Disposal Group
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current liabilities associated with assets held for sale										39	52
Discontinued Operations, Held-for-sale \| Commercial Renewables
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Current liabilities associated with assets held for sale										$ 18	80
Noncontrolling interest balance											$ 18

Duke Energy CORP 10-Q