Stockholders' Equity (Earnings Per Share Data) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Class of Stock [Line Items]
Net (loss) income available to Duke Energy common stockholders excluding impact of participating securities	$ (817)	$ 819	$ 82	$ 1,718
Accumulated preferred stock dividends	(12)
Net (loss) income available to Duke Energy common stockholders excluding impact of participating securities and including accumulated preferred stock dividends	$ (829)	$ 819	$ 82	$ 1,718
Weighted average common shares outstanding – basic (in shares)	735	728	734	728
Equity forwards (in shares)			1
Weighted average common shares outstanding – diluted (in shares)	735	728	735	728
Basic and diluted (in usd per share)	$ (1.13)	$ 1.12	$ 0.11	$ 2.36
Potentially dilutive items excluded from the calculation (in shares)	2	2	2	2
Common Stock
Class of Stock [Line Items]
Dividends declared per common share (in usd per share)	$ 0.945	$ 0.928	$ 1.890	$ 1.855
Preferred stock, Series A
Class of Stock [Line Items]
Dividends declared on preferred stock per depositary share (in usd per share)	0.359	$ 0.307	$ 0.719	$ 0.307
Cumulative dividend rate per annum			5.75%
Price per share (in usd per share)	25		$ 25
Preferred stock, Series B
Class of Stock [Line Items]
Dividends declared on preferred stock per depositary share (in usd per share)			$ 24.917
Cumulative dividend rate per annum			4.875%
Liquidation preference per share (in usd per share)	$ 1,000		$ 1,000