Derivatives and Hedging (Schedule of Offsetting Liabilities) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	$ 433	$ 472
Net amounts presented in Current Liabilities: Other	433	472
Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	115	184
Gross amounts offset		(11)
Net amounts presented in Current Liabilities: Other	115	173
Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	318	288
Gross amounts offset		(12)
Net amounts presented in Current Liabilities: Other	318	276
Duke Energy Carolinas
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	37	35
Net amounts presented in Current Liabilities: Other	37	35
Duke Energy Carolinas | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	36	26
Gross amounts offset		(6)
Net amounts presented in Current Liabilities: Other	36	20
Duke Energy Carolinas | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	1	9
Gross amounts offset		(8)
Net amounts presented in Current Liabilities: Other	1	1
Progress Energy
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		24
Net amounts presented in Current Liabilities: Other		24
Progress Energy | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		19
Gross amounts offset		(5)
Net amounts presented in Current Liabilities: Other		14
Progress Energy | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		5
Gross amounts offset		(5)
Duke Energy Progress
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		10
Net amounts presented in Current Liabilities: Other		10
Duke Energy Progress | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		5
Gross amounts offset		(5)
Duke Energy Progress | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		5
Gross amounts offset		(5)
Duke Energy Florida
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		14
Net amounts presented in Current Liabilities: Other		14
Duke Energy Florida | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		14
Net amounts presented in Current Liabilities: Other		14
Duke Energy Ohio
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	3	5
Duke Energy Ohio | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	1	1
Net amounts presented in Current Liabilities: Other	1	1
Duke Energy Ohio | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	2	4
Net amounts presented in Current Liabilities: Other	2	4
Duke Energy Indiana
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		27
Net amounts presented in Current Liabilities: Other		27
Duke Energy Indiana | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		13
Net amounts presented in Current Liabilities: Other		13
Duke Energy Indiana | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized		14
Net amounts presented in Current Liabilities: Other		14
Piedmont
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	173	139
Net amounts presented in Current Liabilities: Other	173	139
Piedmont | Current liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	24	21
Net amounts presented in Current Liabilities: Other	24	21
Piedmont | Noncurrent liabilities
Offsetting Derivative Liabilities [Abstract]
Gross amounts recognized	149	118
Net amounts presented in Current Liabilities: Other	$ 149	$ 118