Stockholders' Equity (Earnings Per Share Data) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Net Income available to Duke Energy common stockholders	$ 1,270	$ 3,707	$ 2,666
Income (Loss) From Discontinued Operations, net of tax	7	(7)	19
Accumulated preferred stock dividends adjustment	1	(15)	0
Less: Impact of participating securities	2	5	5
Income from continuing operations available to Duke Energy common stockholders	$ 1,262	$ 3,694	$ 2,642
Weighted average common shares outstanding – basic (in shares)	737	729	708
Equity forwards (in shares)	1	0	0
Weighted average common shares outstanding – diluted (in shares)	738	729	708
EPS from continuing operations available to Duke Energy common stockholders
Basic and diluted (usd per share)	$ 1.71	$ 5.07	$ 3.73
Potentially dilutive items excluded from the calculation(in shares)	2	2	2
Dividends declared per share (usd per share)	$ 3.82	$ 3.75	$ 3.64
Series A Preferred Stock
EPS from continuing operations available to Duke Energy common stockholders
Dividends declared on preferred stock (usd per share)	1.437	$ 1.03
Series B Preferred Stock
EPS from continuing operations available to Duke Energy common stockholders
Dividends declared on preferred stock (usd per share)	$ 49.292		$ 0