Organization and Basis of Presentation (Schedule of New Accounting Pronouncements) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings		$ 49,658	$ 49,184	$ 48,083	$ 47,951
Accounting Standards Update [Extensible List]	ASU 2016-13
Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings		16,530	16,241	15,877	15,593
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings		2,680	2,471	4,221	4,108
Retained Earnings | Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings		$ 7,400	$ 7,109	$ 6,747	6,465
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings					120
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Duke Energy Carolinas
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings					16
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Progress Energy
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings					2
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Duke Energy Progress
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings					1
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Duke Energy Florida
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings					1
Cumulative Change in Accounting Principle | Retained Earnings | Revision of Prior Period, Accounting Standards Update, Adjustment | Piedmont
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total pretax impact to Retained Earnings					$ 1